Exon skipping during splicing of dystrophin mRNA precursor due to an intraexon deletion in the dystrophin gene of Duchenne muscular dystrophy kobe.

Recent molecular studies have shown that in a patient with Duchenne muscular dystrophy (DMD) Kobe, the size of exon 19 of the dystrophin gene was reduced to 36 bp due to the deletion of 52 bp out of 88 bp of the exon. The consensus sequences at the 5' and 3' splice sites of exon 19 were unaltered (Matsuo, M., et al. 1990. Biochem. Biophys. Res. Commun. 170:963-967). To further elucidate the molecular nature of the defect, we examined the primary structure of cytoplasmic dystrophin mRNA of the DMD Kobe patient across the junctions of exons 18, 19, and 20 by gel electrophoresis and sequencing of polymerase chain reaction-amplified cDNA. The mRNA coding for dystrophin was reverse transcribed using random primers, and the cDNA was then enzymatically amplified in vitro. The targeted fragment was smaller than expected from the genomic DNA analysis. By sequencing of the amplified product, we found that exon 18 was joined directly to exon 20, so that exon 19 was completely absent, suggesting that this exon was skipped during processing of the dystrophin mRNA precursor. All other bases in the amplified product were unaltered. Therefore, the data strongly suggest that the internal exon deletion generates an abnormally spliced mRNA in which the sequence of exon 18 is joined to the sequence of exon 20. We propose that the deletion is responsible for abnormal processing of the DMD Kobe allele. This finding has important implications regarding the determinants of a functional splice site.

Recent molecular studies have shown that in a patient with

    Duchenne muscular dystrophy (DMD) Kobe
    DIAGNOSIS

,

    the size of exon 19 of the dystrophin gene was reduced to 36 bp
    GENETICS

 due to the

    deletion of 52 bp out of 88 bp of the exon
    GENETICS

.

    The consensus sequences at the 5' and 3' splice sites of exon 19 were unaltered
    GENETICS

 (Matsuo, M., et al. 1990. Biochem. Biophys. Res. Commun. 170:963-967). To further elucidate the molecular nature of the defect, we

    examined the primary structure of cytoplasmic dystrophin mRNA
    PARACLINICAL

 of the

    DMD Kobe
    DIAGNOSIS

 patient

    across the junctions of exons 18, 19, and 20
    PARACLINICAL

 by

    gel electrophoresis and sequencing of polymerase chain reaction-amplified cDNA
    PARACLINICAL

. The

    mRNA coding for dystrophin was reverse transcribed using random primers
    PARACLINICAL

, and the cDNA was then

    enzymatically amplified in vitro
    PARACLINICAL

. The targeted fragment was smaller than expected from the

    genomic DNA analysis
    PARACLINICAL

. By

    sequencing of the amplified product
    PARACLINICAL

, we found that

    exon 18 was joined directly to exon 20, so that exon 19 was completely absent
    GENETICS

, suggesting that

    this exon was skipped during processing of the dystrophin mRNA precursor
    GENETICS

.

    All other bases in the amplified product were unaltered
    GENETICS

. Therefore, the data strongly suggest that the

    internal exon deletion
    GENETICS

 generates an

    abnormally spliced mRNA in which the sequence of exon 18 is joined to the sequence of exon 20
    GENETICS

. We propose that the deletion is responsible for

    abnormal processing of the DMD Kobe allele
    GENETICS

. This finding has important implications regarding the determinants of a functional splice site.

Duchenne muscular dystrophy (DMD) Kobe
DMD Kobe


Sequences of junction fragments in the deletion-prone region of the dystrophin gene.

The Duchenne muscular dystrophy locus is remarkable in that it shows a high mutation rate and the majority of mutations found are deletions. These deletions are generated as meiotic as well as mitotic events and occur preferentially in the central region of the gene. Nothing is known so far about the mechanisms involved. This paper reports the first sequencing of deletion junctions in the dystrophin gene. The data from a study of two patients with deletions in the central region of dystrophin show the breakpoints to lie in regions of introns in which stretches of dA-dT are seen. The relationship between these observations and possible mechanisms for the mutations is discussed.

The

    Duchenne muscular dystrophy locus
    DIAGNOSIS

 is remarkable in that it shows a high mutation rate and the majority of mutations found are

    deletions
    GENETICS

. These deletions are generated as meiotic as well as mitotic events and occur preferentially in the central region

    of the gene
    GENETICS

. Nothing is known so far about the mechanisms involved. This paper reports the first

    sequencing of deletion junctions in the dystrophin gene
    PARACLINICAL

. The data from a study of two patients with

    deletions in the central region of dystrophin
    GENETICS

 show the

    breakpoints to lie in regions of introns in which stretches of dA-dT are seen
    GENETICS

. The relationship between these observations and possible mechanisms for the mutations is discussed.


The value of deletion analysis for carrier detection in Duchenne muscular dystrophy (DMD).

We performed genetic analysis for carrier detection for several at-risk females in a four-generation Duchenne muscular dystrophy (DMD) pedigree using deletion analysis. We demonstrated that dosage analysis is a suitable alternative method to determine the carrier status of female relatives of DMD patients shown to have a deletion within the DMD gene. Subsequently, we diagnosed an affected male fetus for an at-risk female shown to be a DMD carrier by deletion analysis. The usefulness of deletion and linkage analysis are compared. In this family, linkage analysis was complicated by the unavailability of key family members, two recombination events and by previously undisclosed nonpaternity. We found that dosage analysis was more efficient than linkage for carrier evaluation in this family.

We performed

    genetic analysis
    PARACLINICAL

 for carrier detection for several at-risk

    females
    GENDER

 in a

    four-generation Duchenne muscular dystrophy (DMD)
    FAMILY

 pedigree using

    deletion analysis
    PARACLINICAL

. We demonstrated that

    dosage analysis
    PARACLINICAL

 is a suitable alternative method to determine the carrier status of

    female
    GENDER

 relatives of

    DMD
    DIAGNOSIS

 patients shown to have a

    deletion within the DMD gene
    GENETICS

. Subsequently, we diagnosed an

    affected male fetus for an at-risk female
    FAMILY

    shown to be a DMD carrier
    FAMILY

 by

    deletion analysis
    PARACLINICAL

. The usefulness of

    deletion and linkage analysis
    PARACLINICAL

 are compared. In this family,

    linkage analysis
    PARACLINICAL

 was complicated by the

    unavailability of key family members
    FAMILY

,

    two recombination events
    FAMILY

 and by

    previously undisclosed nonpaternity
    FAMILY

. We found that

    dosage analysis
    PARACLINICAL

 was more efficient than

    linkage
    PARACLINICAL

 for

    carrier evaluation
    PARACLINICAL

 in this family.


Myoblast transfer therapy for Duchenne muscular dystrophy.

A randomly selected extensor digitorum brevis (EDB) muscle in each of three Duchenne muscular dystrophy (DMD) boys aged 9 to 10 was injected with approximately 8 x 10(6) myoblasts. The contralateral EDBs were sham-injected with carrier solution. Donor myoblasts were derived from cell culture of muscle biopsies from the normal ward or normal brothers of the recipients. Cyclosporine (CsA) treatment began two days before myoblast injection and continued for three months. Three days prior to myoblast injection and three months after, the isometric twitch and maximum voluntary contraction of the left and the right EDBs were measured. Myoblast-injected EDBs showed increases in tensions whereas sham-injected EDBs showed reductions. Both immunocytochemical staining and immunoblot revealed dystrophin in the myoblast-injected EDBs. Dystrophic characteristics such as fiber splitting, central nucleation, phagocytic necrosis, variation in fiber shape and size, and infiltration of fat and connective tissues were less frequently observed in these muscles. Sham-injected EDBs exhibited significant structural and functional degeneration and no dystrophin. Throughout the study, there was no sign of erythema, swelling or tenderness at the injection sites. Serial laboratory evaluation including electrolytes, creatinine, and urea did not reveal any significant changes before or after myoblast transfer. We conclude that myoblast transfer therapy is a safe and efficacious procedure to improve the biochemistry, structure, and function of degenerative EDB muscles in DMD.

A randomly selected

    extensor digitorum brevis (EDB) muscle
    DIAGNOSIS

 in each of three

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

    boys
    GENDER

    aged 9 to 10
    AGE

 was

    injected with approximately 8 x 10(6) myoblasts
    MEDICATION

. The contralateral EDBs were

    sham-injected with carrier solution
    MEDICATION

.

    Donor myoblasts were derived from cell culture of muscle biopsies
    MICROSCOPIC

 from the normal ward or normal brothers of the recipients.

    Cyclosporine (CsA) treatment began two days before myoblast injection and continued for three months
    MEDICATION

. Three days prior to

    myoblast injection
    MEDICATION

 and three months after, the

    isometric twitch and maximum voluntary contraction of the left and the right EDBs were measured
    SYMPTOMS

.

    Myoblast-injected EDBs
    MEDICATION

 showed

    increases in tensions
    SYMPTOMS

 whereas

    sham-injected EDBs showed reductions
    MEDICATION

. Both

    immunocytochemical staining
    PARACLINICAL

 and

    immunoblot
    PARACLINICAL

 revealed

    dystrophin in the myoblast-injected EDBs
    MICROSCOPIC

.

    Dystrophic characteristics
    SYMPTOMS

 such as

    fiber splitting
    SYMPTOMS

,

    central nucleation
    MICROSCOPIC

,

    phagocytic necrosis
    MICROSCOPIC

,

    variation in fiber shape and size
    SYMPTOMS

, and

    infiltration of fat and connective tissues
    MICROSCOPIC

 were less frequently observed

    in these muscles
    SYMPTOMS

.

    Sham-injected EDBs
    NEG_FINDINGS

 exhibited

    significant structural and functional degeneration
    SYMPTOMS

 and

    no dystrophin
    NEG_FINDINGS

. Throughout the study, there was

    no sign of erythema, swelling or tenderness at the injection sites
    NEG_FINDINGS

.

    Serial laboratory evaluation including electrolytes, creatinine, and urea did not reveal any significant changes before or after myoblast transfer
    NEG_FINDINGS

. We conclude that

    myoblast transfer therapy
    MEDICATION

 is a safe and efficacious procedure to

    improve the biochemistry, structure, and function of degenerative EDB muscles
    SYMPTOMS

 in

    DMD
    DIAGNOSIS

.

extensor digitorum brevis (EDB) muscle
Duchenne muscular dystrophy (DMD)
DMD


Screening of male patients with autosomal recessive Duchenne dystrophy through dystrophin and DNA studies.

Previously we estimated that about 2.5-4% of isolated male patients diagnosed as Duchenne dystrophy (DMD) may have the autosomal recessive form (AR-DMD). Such cases can be distinguished from X-linked DMD through the analysis of dystrophin. Fifty DMD patients from 47 families were investigated for dystrophin and DNA deletions. Based on our results, we estimate that the frequency of AR-DMD may be about 8-12% among male patients diagnosed as DMD in whom X-linked inheritance could not be confirmed through pedigree data, serum enzymes in female relatives or DNA studies. Such an estimate must be confirmed in a larger sample; however, it shows the importance of assessing dystrophin in all patients diagnosed as DMD in whom X-linked inheritance cannot be proved, since the distinction between these 2 forms has implications for genetic counseling.

Previously we estimated that about 2.5-4% of isolated

    male
    GENDER

 patients diagnosed as

    Duchenne dystrophy (DMD)
    DIAGNOSIS

 may have the

    autosomal recessive form (AR-DMD)
    DIAGNOSIS

. Such cases can be distinguished from

    X-linked DMD
    GENETICS

 through the

    analysis of dystrophin
    PARACLINICAL

. Fifty

    DMD
    DIAGNOSIS

 patients from 47 families were investigated for

    dystrophin and DNA deletions
    PARACLINICAL

. Based on our results, we estimate that the frequency of

    AR-DMD
    DIAGNOSIS

 may be about 8-12% among

    male
    GENDER

 patients diagnosed as

    DMD
    DIAGNOSIS

 in whom

    X-linked inheritance could not be confirmed through pedigree data
    NEG_FINDINGS

,

    serum enzymes in female relatives
    BIOCHEMICAL

 or

    DNA studies
    PARACLINICAL

. Such an estimate must be confirmed in a larger sample; however, it shows the importance of

    assessing dystrophin
    PARACLINICAL

 in all patients diagnosed as

    DMD
    DIAGNOSIS

 in whom

    X-linked inheritance cannot be proved
    NEG_FINDINGS

, since the distinction between these 2 forms has implications for

    genetic counseling
    MEDICATION

.

Duchenne dystrophy (DMD)
autosomal recessive form (AR-DMD)
DMD
AR-DMD
DMD
DMD


[Myocardial involvement in 2 women, carriers of Duchenne de Boulogne muscular dystrophy].

Duchenne muscular dystrophy is the commonest genetic muscular disease. The prognosis, which depends on cardiac involvement, is poor. In boys, this takes the form of a hypokinetic cardiomyopathy particularly affecting the postero-lateral wall of the left ventricle which then dilates. The recent identification of the gene which transmits the disease on the X chromosome and of the coded protein, dystrophin, has improved our understanding of the disease. We report two cases of isolated cardiac involvement in two female carriers of the disease, classically thought to be unaffected. They presented with apparently idiopathic dilated cardiomyopathies. These cases show that Duchenne muscular dystrophy is an original example of a genetically determined diffuse muscular disease with cardiac involvement.

    Duchenne muscular dystrophy
    DIAGNOSIS

 is the commonest

    genetic muscular disease
    DIAGNOSIS

. The prognosis, which depends on

    cardiac involvement
    SYMPTOMS

, is poor. In

    boys
    GENDER

, this takes the form of a

    hypokinetic cardiomyopathy particularly affecting the postero-lateral wall of the left ventricle which then dilates
    SYMPTOMS

. The recent

    identification of the gene which transmits the disease on the X chromosome and of the coded protein, dystrophin
    GENETICS

, has improved our understanding of the disease. We report two cases of

    isolated cardiac involvement
    SYMPTOMS

 in two

    female
    GENDER

    carriers of the disease
    FAMILY

,

    classically thought to be unaffected
    NEG_FINDINGS

. They presented with

    apparently idiopathic dilated cardiomyopathies
    SYMPTOMS

. These cases show that

    Duchenne muscular dystrophy
    DIAGNOSIS

 is an original example of a

    genetically determined
    GENETICS

    diffuse muscular disease
    DIAGNOSIS

 with

    cardiac involvement
    SYMPTOMS

.

Duchenne muscular dystrophy
genetic muscular disease
Duchenne muscular dystrophy
diffuse muscular disease


Studies of an L-rod sublaminar wire spinal fusion.

The spine of a 25-year-old man with Duchenne muscular dystrophy was studied postmortem, 8 years after spine fusion with L-rods and sublaminar wires. The fusion was solid. Instrumentation appeared to have had no adverse effects on the spinal cord or meninges or in the epidural space. When wire removal from the spinal canal and fusion mass was studied, increased penetration of the wires into the spinal canal was noted.

The spine of a

    25-year-old
    AGE

    man
    GENDER

 with

    Duchenne muscular dystrophy
    DIAGNOSIS

 was studied

    postmortem
    PARACLINICAL

, 8 years after

    spine fusion with L-rods and sublaminar wires
    MEDICATION

. The

    fusion was solid
    SYMPTOMS

.

    Instrumentation appeared to have had no adverse effects on the spinal cord or meninges or in the epidural space
    NEG_FINDINGS

. When

    wire removal from the spinal canal and fusion mass was studied
    PARACLINICAL

,

    increased penetration of the wires into the spinal canal
    SYMPTOMS

 was noted.


[Two long-living brothers of dystrophin-related muscular dystrophy with an in-frame deletion of exon 3 of the dystrophin gene--clinical features and diagnosis].

Two long-living brothers of dystrophin-related muscular dystrophy with an in-frame deletion of exon 3 of the dystrophin gene were described. Weakness of the lower extremities and pseudohypertrophy of calf muscles began at the age of 2 years in the elder brother and 4 years in the younger brother, respectively. Clinical symptoms progressed rapidly and both of them lost ambulation and became wheelchair bound at the age of 11-12 years. However, the progression of the disease process slowed in late teens, and now at the age of 36 and 33 years, respectively, they do not have respiratory or cardiac insufficiency, although they are disabled severely. Southern blotting with the entire dystrophin cDNAs, cDNA 1-2a, 2b-3, 4-5a, 5b-7, 8, and 9-14, revealed a single deletion of exon 3 in the 2 brothers. The mother was shown to be a heterozygote for this mutation. The unique clinical features of these brothers were presumed due to the following 2 factors: (1) a single deletion of exon 3 is an in-frame deletion of the dystrophin gene, and (2) exon 3 corresponds to a unique domain of the dystrophin molecule; the amino-terminal region which is highly homologous to the actin-binding-region of alpha-actinin. We consider that these 2 brothers are compatible with the so-called frame-shift hypothesis of Duchenne/Becker muscular dystrophy (DMD/BMD) phenotype, although they are diagnosed DMD by the classification method based on the patients' age of becoming permanently wheelchair bound.

Two

    long-living
    AGE

    brothers
    GENDER

 of

    dystrophin-related muscular dystrophy
    DIAGNOSIS

 with an

    in-frame deletion of exon 3 of the dystrophin gene
    GENETICS

 were described.

    Weakness of the lower extremities
    SYMPTOMS

 and

    pseudohypertrophy of calf muscles
    SYMPTOMS

 began

    at the age of 2 years
    AGE

 in the

    elder brother
    AGE

    and 4 years
    AGE

 in the

    younger brother
    AGE

, respectively. Clinical symptoms progressed rapidly and both of them

    lost ambulation
    SYMPTOMS

 and became

    wheelchair bound
    MEDICATION

 at the

    age of 11-12 years
    AGE

. However, the progression of the disease process slowed in

    late teens
    AGE

, and now at the

    age of 36 and 33 years
    AGE

, respectively, they do

    not have respiratory or cardiac insufficiency
    NEG_FINDINGS

, although they are

    disabled severely
    SYMPTOMS

.

    Southern blotting with the entire dystrophin cDNAs, cDNA 1-2a, 2b-3, 4-5a, 5b-7, 8, and 9-14
    PARACLINICAL

, revealed a

    single deletion of exon 3
    GENETICS

 in the 2

    brothers
    GENDER

. The

    mother was shown to be a heterozygote for this mutation
    FAMILY

. The unique clinical features of these

    brothers
    GENDER

 were presumed due to the following 2 factors: (1) a

    single deletion of exon 3 is an in-frame deletion of the dystrophin gene
    GENETICS

, and (2)

    exon 3 corresponds to a unique domain of the dystrophin molecule; the amino-terminal region which is highly homologous to the actin-binding-region of alpha-actinin
    GENETICS

. We consider that these 2

    brothers
    GENDER

 are compatible with the so-called frame-shift hypothesis of

    Duchenne/Becker muscular dystrophy (DMD/BMD)
    DIAGNOSIS

 phenotype, although they are diagnosed

    DMD
    DIAGNOSIS

 by the classification method based on the patients' age of becoming

    permanently wheelchair bound
    MEDICATION

.

Weakness of the lower extremities
pseudohypertrophy of calf muscles
lost ambulation
disabled severely

wheelchair bound
permanently wheelchair bound


Characterisation of a Xp21 microdeletion syndrome in a 2-year-old boy with muscular dystrophy, glycerol kinase deficiency and adrenal hypoplasia congenita.

We report a 2-year-old boy with Duchenne muscular dystrophy (DMD), glycerol kinase deficiency (GK) and adrenal hypoplasia congenita (AHC). At three weeks of age, the patient was hospitalized for the first time with symptoms of hypotone dehydration because of AHC. At present, he shows severe muscular hypotonia and developmental delay. The patient and his family were referred to us for prenatal diagnosis and carrier testing in the mother of the patient and the mother's sister, respectively. The patient's DNA was examined by Southern blot and polymerase chain reaction analyses, using cDNA and genomic probes within and around the dystrophin (DYS) locus. A deletion was revealed, spanning DXS28, the whole dystrophin locus, DXS84 and DXS148, whereas DXS67, DXS68 (pter) and OTC (cen) were found to be retained. The cytogenetically visible microdeletion was also seen in the patient's mother, but not in the mother's sister or the patient's maternal grandmother. Our findings support the locus order pter-DXS67-DXS68-DXS28-AHC-GK-DMD-cen.

We report a

    2-year-old
    AGE

    boy
    GENDER

 with

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

,

    glycerol kinase deficiency (GK)
    BIOCHEMICAL

 and

    adrenal hypoplasia congenita (AHC)
    DIAGNOSIS

. At

    three weeks of age
    AGE

, the patient was hospitalized for the first time with

    symptoms of hypotone dehydration
    SYMPTOMS

 because of

    AHC
    DIAGNOSIS

. At present,

    he
    GENDER

 shows

    severe muscular hypotonia
    SYMPTOMS

 and

    developmental delay
    SYMPTOMS

. The patient and

    his
    GENDER

 family were referred to us for

    prenatal diagnosis
    PARACLINICAL

 and

    carrier testing
    PARACLINICAL

 in the

    mother of the patient and the mother's sister
    FAMILY

, respectively.

    The patient's DNA was examined by Southern blot and polymerase chain reaction analyses, using cDNA and genomic probes within and around the dystrophin (DYS) locus
    PARACLINICAL

. A

    deletion was revealed, spanning DXS28, the whole dystrophin locus, DXS84 and DXS148
    GENETICS

, whereas

    DXS67, DXS68 (pter) and OTC (cen) were found to be retained
    GENETICS

. The

    cytogenetically visible microdeletion was also seen in the patient's mother, but not in the mother's sister or the patient's maternal grandmother
    GENETICS

. Our findings support the locus order

    pter-DXS67-DXS68-DXS28-AHC-GK-DMD-cen
    GENETICS

.

Duchenne muscular dystrophy (DMD)
adrenal hypoplasia congenita (AHC)
AHC

symptoms of hypotone dehydration
severe muscular hypotonia
developmental delay


Prenatal deletion detection in a sporadic case of Duchenne muscular dystrophy without genotype information from the affected individual.

We describe the application of deletion screening by amplification of deletion-prone exons via polymerase chain reaction (PCR) in a family with a sporadic case of Duchenne muscular dystrophy (DMD). No DNA was available from the affected patient who died 12 years beforehand at the age of 18 years. Material obtained prenatally from two male fetuses exhibited an identical deletion. These findings effectively transformed a sporadic case into a familial case and a numerical carrier risk was substituted by obligate carrier status. Additionally an indirect genotype analysis was replaced by the possibility of direct DNA analysis. Genetic counselling, formerly based upon incomplete data, can now be aided by precise risk assessment.

We describe the application of

    deletion screening by amplification of deletion-prone exons via polymerase chain reaction (PCR)
    PARACLINICAL

 in a

    family with a sporadic case of Duchenne muscular dystrophy (DMD)
    FAMILY

.

    No DNA was available
    NEG_FINDINGS

 from the affected patient who

    died
    SYMPTOMS

 12 years beforehand at the

    age of 18 years
    AGE

.

    Material obtained prenatally
    PARACLINICAL

 from two

    male
    GENDER

    fetuses exhibited an identical deletion
    FAMILY

. These findings effectively transformed a sporadic case into a

    familial case
    FAMILY

 and a

    numerical carrier risk
    FAMILY

 was substituted by

    obligate carrier status
    FAMILY

. Additionally an

    indirect genotype analysis
    PARACLINICAL

 was replaced by the possibility of

    direct DNA analysis
    PARACLINICAL

.

    Genetic counselling
    MEDICATION

, formerly based upon incomplete data, can now be aided by precise risk assessment.


Familial occurrence of Duchenne dystrophy through paternal lines in four families.

In a survey of 454 families with patients affected with Duchenne muscular dystrophy (DMD) we have found 4 genealogies with 2 or more affected patients who were related through paternal lines. In 1 of these families, 2 affected cousins showed different DNA deletions suggesting 2 independent mutations; in the other 2, in which only the propositus could be studied DNA deletions were also detected in the dystrophin gene. In the last one, with 3 affected patients, no DNA deletions were detected but immunohistochemical study of muscle biopsies showed a negative dystrophin pattern typical of DMD. Although one of these families might have occurred by chance, the probability of finding the other 3 in our sample of families with DMD patients constitutes a rare event. It is suggested that other mechanisms, such as the presence of transposable elements in other sites of the genome, could be responsible in some families, for a greater predisposition for the occurrence of pathogenic deletions, duplications or mutations.

In a survey of 454 families with patients affected with

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

 we have found 4

    genealogies with 2 or more affected patients who were related through paternal lines
    FAMILY

. In 1 of these families,

    2 affected cousins showed different DNA deletions suggesting 2 independent mutations
    FAMILY

; in the other 2, in which only the propositus could be studied

    DNA deletions were also detected in the dystrophin gene
    GENETICS

. In the last one, with 3 affected patients,

    no DNA deletions were detected
    NEG_FINDINGS

 but

    immunohistochemical study of muscle biopsies
    PARACLINICAL

 showed a

    negative dystrophin pattern typical of DMD
    NEG_FINDINGS

. Although one of these families might have occurred by chance, the probability of finding the other 3 in our sample of families with

    DMD
    DIAGNOSIS

 patients constitutes a rare event. It is suggested that other mechanisms, such as the presence of

    transposable elements in other sites of the genome
    GENETICS

, could be responsible in some families, for a greater predisposition for the occurrence of

    pathogenic deletions, duplications or mutations
    GENETICS

.


Possibilities and limitations of carrier diagnosis in families with Duchenne muscular dystrophy caused by deletions in the major hot spot region using pulsed-field gel electrophoresis.

The cDNA probes cf56a, b identify deletions in 45% of the investigated patients with Duchenne and Becker muscular dystrophy (DMD/BMD). But carrier detection by junction fragments using normal gel electrophoresis conditions separating fragments up to a size of about 25 kilobases is possible only in selected cases. We, therefore, applied separation of Sfi I-digested DNA by rotating-field gel electrophoresis (RFE) in combination with Southern blot transfer and hybridization using cf56a for this purpose. In this study we compared hybridizing fragments of DNA from three DMD families with different deletion patterns: distal to the Sfi I-site F located between exon 48/49 (family A), proximal to the Sfi I-site F including the P20 intron (family B), and bridging the Sfi I-site F (family C). Junction fragments in the DNA of 2 affected boys and their mothers were detected in families B and C. Carrier determination on this basis was performed for family C. Given these three families are representative for other families with similar deletions, it will be possible to offer carrier diagnosis using RFE in 38% of the studied families with DMD/BMD caused by deletions in the major hot spot region.

The cDNA probes cf56a, b identify deletions in 45% of the investigated patients with

    Duchenne and Becker muscular dystrophy (DMD/BMD)
    DIAGNOSIS

. But carrier detection by junction fragments using

    normal gel electrophoresis
    PARACLINICAL

 conditions separating fragments up to a size of about 25 kilobases is possible only in selected cases. We, therefore, applied

    separation of Sfi I-digested DNA by rotating-field gel electrophoresis (RFE)
    PARACLINICAL

 in combination with

    Southern blot transfer
    PARACLINICAL

 and

    hybridization using cf56a
    PARACLINICAL

 for this purpose. In this study we compared

    hybridizing fragments of DNA
    PARACLINICAL

 from three

    DMD
    DIAGNOSIS

 families with different

    deletion patterns: distal to the Sfi I-site F located between exon 48/49
    GENETICS

 (family A),

    proximal to the Sfi I-site F including the P20 intron
    GENETICS

 (family B), and

    bridging the Sfi I-site F
    GENETICS

 (family C).

    Junction fragments in the DNA of
    MICROSCOPIC

 2 affected

    boys
    GENDER

 and their mothers were detected in families B and C.

    Carrier determination
    PARACLINICAL

 on this basis was performed for family C. Given these three families are representative for other families with similar deletions, it will be possible to offer

    carrier diagnosis
    PARACLINICAL

 using

    RFE
    PARACLINICAL

 in 38% of the studied families with

    DMD/BMD
    DIAGNOSIS

 caused by

    deletions in the major hot spot region
    GENETICS

.


X-linked and FSH dystrophies in one family.

A family is reported in which the father was affected by facioscapulohumeral muscular dystrophy FSHD. One son was affected by Duchenne muscular dystrophy (DMD). The second son died at the age of 3 yr of a severe primary muscle disease and it is suggested that this was the outcome of dual expression of the two conditions.

A family is reported

    in which the father was affected by facioscapulohumeral muscular dystrophy FSHD
    FAMILY

.

    One son was affected by Duchenne muscular dystrophy (DMD)
    FAMILY

. The

    second son died
    FAMILY

    at the age of 3 yr
    AGE

    of a severe primary muscle disease
    FAMILY

 and it is suggested that this was the outcome of

    dual expression of the two conditions
    FAMILY

.


[A benign variant of the course of Duchenne muscular dystrophy in a child with short stature].

The authors describe a case of a benign variety of progressive Duchenne type muscular dystrophy in a 8-year-old short-stature boy. Provide the electromyographic and electroneuromyographic data, measurements of the growth hormone in blood serum and osseous age. Make suggestions about coupled inheritance of progressive Duchenne type muscular dystrophy and short stature . The latter one is likely to be attended by a decrease of anabolic processes, which may determine a more benign course of the myodystrophic process.

The authors describe a case of a

    benign variety of progressive Duchenne type muscular dystrophy
    DIAGNOSIS

 in a

    8-year-old
    AGE

    short-stature
    SYMPTOMS

    boy
    GENDER

. Provide the

    electromyographic and electroneuromyographic data
    PARACLINICAL

,

    measurements of the growth hormone in blood serum
    BIOCHEMICAL

 and osseous

    age
    PARACLINICAL

. Make suggestions about

    coupled inheritance of progressive Duchenne type muscular dystrophy
    GENETICS

 and

    short stature
    SYMPTOMS

 . The latter one is likely to be attended by a

    decrease of anabolic processes
    BIOCHEMICAL

, which may determine a more

    benign course of the myodystrophic process
    NEG_FINDINGS

.


An isolated case of Duchenne muscular dystrophy (DMD) in a female with a deletion of DMD cDNA.

An isolated case of Duchenne muscular dystrophy (DMD) in a female who has a deletion of the DMD locus is described. This patient was a 26-year-old woman born to unrelated, healthy parents. She was initially examined at age 6 because of a waddling gait. At age 15, pseudohypertrophy of calves and pes equinus were observed along with proximal muscular weakness and wasting. Her serum creatine kinase level was high and histological evidence of muscular dystrophy was apparent on muscle biopsy. The patient was ambulant at age 15 and progression of motor disability has been slow. Chromosomal studies revealed a normal karyotype, and mental retardation is moderate. DNA analysis at age 26 revealed that she has a deletion of DMD cDNA 8 mapped within Xp21 and is heterozygous for the deletion. Since diagnosis of DMD is now dependent on the evidence of mutation or deletion at Xp21, this patient is thought to have a form of DMD. Expression of the DMD gene in the heterozygous state might be due to random but unequal lyonization.

An isolated case of

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

 in a

    female
    GENDER

 who has a

    deletion of the DMD locus
    GENETICS

 is described. This patient was a

    26-year-old
    AGE

    woman
    GENDER

 born to unrelated, healthy parents.

    She
    GENDER

 was initially examined at

    age 6
    AGE

 because of a

    waddling gait
    SYMPTOMS

. At

    age 15
    AGE

,

    pseudohypertrophy of calves
    SYMPTOMS

 and

    pes equinus
    SYMPTOMS

 were observed along with

    proximal muscular weakness
    SYMPTOMS

 and

    wasting
    SYMPTOMS

.

    Her
    GENDER

    serum creatine kinase level was high
    BIOCHEMICAL

 and

    histological evidence of muscular dystrophy
    SYMPTOMS

 was apparent on

    muscle biopsy
    PARACLINICAL

. The patient was

    ambulant
    MEDICATION

 at

    age 15
    AGE

 and

    progression of motor disability has been slow
    SYMPTOMS

.

    Chromosomal studies
    PARACLINICAL

 revealed a

    normal karyotype
    NEG_FINDINGS

, and

    mental retardation is moderate
    SYMPTOMS

.

    DNA analysis
    PARACLINICAL

 at

    age 26
    AGE

 revealed that

    she
    GENDER

 has a

    deletion of DMD cDNA 8 mapped within Xp21
    GENETICS

 and is

    heterozygous for the deletion
    GENETICS

. Since diagnosis of

    DMD
    DIAGNOSIS

 is now dependent on the evidence of

    mutation or deletion at Xp21
    GENETICS

, this patient is thought to have a form of

    DMD
    DIAGNOSIS

.

    Expression of the DMD gene in the heterozygous state
    GENETICS

 might be due to

    random but unequal lyonization
    GENETICS

.

Duchenne muscular dystrophy (DMD)
DMD
DMD


[Electrocardiographic evaluation of myocardial co-involvement in Duchenne muscular dystrophy: prognostic implications in a case with multiple localizations].

After a review of the literature on myocardial involvement (MI) in Duchenne's progressive muscular dystrophy (DMD), the authors report a case with an extensive MI. This severe myocardial functional impairment is a poor index in the prognosis of DMD. The authors emphasize the use of echocardiography in the screening of MI in DMD.

After a review of the literature on

    myocardial involvement (MI)
    SYMPTOMS

 in

    Duchenne's progressive muscular dystrophy (DMD)
    DIAGNOSIS

, the authors report a case with an

    extensive MI
    SYMPTOMS

. This

    severe myocardial functional impairment
    SYMPTOMS

 is a poor index in the prognosis of

    DMD
    DIAGNOSIS

. The authors emphasize the use of

    echocardiography
    PARACLINICAL

 in the screening of

    MI
    DIAGNOSIS

 in

    DMD
    DIAGNOSIS

.

myocardial involvement (MI)
extensive MI
severe myocardial functional impairment


A manifesting carrier of Duchenne muscular dystrophy with severe myocardial symptoms.

A 42-year-old so-called manifesting carrier of Duchenne muscular dystrophy (DMD), whose first complaints were severe myocardial symptoms, is described. Immunohistochemical study using anti-dystrophin anti-serum and analysis of cloned segments of X chromosome DNA were performed. Her two sons and one of her brothers appear to have had the same disease. She was admitted to the hospital complaining of dyspnoea, back pain and palpitations and was first diagnosed as having myocardial infarction. However, this diagnosis was excluded. The echocardiogram showed diffuse abnormalities of myocardial function. Serum enzymes were increased. Minimal weakness and decreased deep tendon reflexes were detected in her left lower extremity. Muscle biopsy revealed a small number of necrotic fibres. Immunohistochemical study using anti-dystrophin antiserum showed a mosaic pattern of the surface membrane. Analysis of cloned segments of X chromosome DNA from the patient and her son showed the XmnI(Asp) alleles of pERT 87-15 and the TaqI alleles of pERT 87-8 in both patients.

A

    42-year-old
    AGE

 so-called manifesting carrier of

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

, whose first complaints were

    severe myocardial symptoms
    SYMPTOMS

, is described.

    Immunohistochemical study using anti-dystrophin anti-serum
    PARACLINICAL

 and

    analysis of cloned segments of X chromosome DNA
    PARACLINICAL

 were performed.

    Her
    GENDER

    two sons and one of her brothers appear to have had the same disease
    FAMILY

.

    She
    GENDER

 was admitted to the hospital complaining of

    dyspnoea
    SYMPTOMS

,

    back pain
    SYMPTOMS

 and

    palpitations
    SYMPTOMS

 and was first diagnosed as having

    myocardial infarction
    SYMPTOMS

.

    However, this diagnosis was excluded
    NEG_FINDINGS

. The

    echocardiogram
    PARACLINICAL

 showed

    diffuse abnormalities of myocardial function
    SYMPTOMS

.

    Serum enzymes were increased
    BIOCHEMICAL

.

    Minimal weakness
    SYMPTOMS

 and

    decreased deep tendon reflexes were detected in her left lower extremity
    SYMPTOMS

.

    Muscle biopsy
    PARACLINICAL

 revealed a

    small number of necrotic fibres
    MICROSCOPIC

.

    Immunohistochemical study using anti-dystrophin antiserum
    PARACLINICAL

 showed a

    mosaic pattern of the surface membrane
    MICROSCOPIC

.

    Analysis of cloned segments of X chromosome DNA from the patient and her son
    PARACLINICAL

 showed

    the XmnI(Asp) alleles of pERT 87-15 and the TaqI alleles of pERT 87-8
    GENETICS

 in both patients.


Normal dystrophin in McLeod myopathy.

Dystrophin and its gene were studied in a patient with McLeod syndrome. This X-linked recessive myopathy has been localized to Xp21, as has the Duchenne muscular dystrophy gene locus, which codes for dystrophin. Histopathological study of the patient's muscle showed mild subclinical myopathy. Immunological studies of dystrophin in two separate biopsy specimens and analysis of dystrophin gene DNA from a blood sample did not detect an abnormality. This suggests that the Duchenne muscular dystrophy gene, albeit close to the McLeod locus, is not involved in McLeod myopathy.

Dystrophin and its gene were studied in a patient with

    McLeod syndrome
    DIAGNOSIS

. This

    X-linked recessive myopathy
    GENETICS

 has been localized to

    Xp21
    GENETICS

, as has the

    Duchenne muscular dystrophy gene locus
    DIAGNOSIS

, which codes

    for dystrophin
    GENETICS

.

    Histopathological study of the patient's muscle
    PARACLINICAL

 showed

    mild subclinical myopathy
    SYMPTOMS

.

    Immunological studies of dystrophin in two separate biopsy specimens
    PARACLINICAL

 and

    analysis of dystrophin gene DNA from a blood sample
    PARACLINICAL

    did not detect an abnormality
    NEG_FINDINGS

. This suggests that the

    Duchenne muscular dystrophy gene
    NEG_FINDINGS

    , albeit close to the McLeod locus
    GENETICS

, is not involved in

    McLeod myopathy
    DIAGNOSIS

.

McLeod syndrome
Duchenne muscular dystrophy gene locus
McLeod myopathy

X-linked recessive myopathy
Xp21
for dystrophin
, albeit close to the McLeod locus

did not detect an abnormality
Duchenne muscular dystrophy gene


Quadriceps myopathy: forme fruste of Becker muscular dystrophy.

We examined dystrophin, the protein product of the Duchenne muscular dystrophy gene, in muscle biopsy specimens from 4 male patients with quadriceps myopathy, all of whom showed a mild and slowly progressive myopathy confined to the quadriceps muscles. All 4 patients had clear abnormalities of dystrophin, and were diagnosed as having Becker muscular dystrophy by both immunofluorescence and immunoblot examinations; that is, dystrophin of an abnormal molecular mass was visualized in muscle cryosections as "patchy" or discontinuous immunostaining at the surface membrane of the muscle fibers. One patient had a brother who showed widespread myopathic changes consistent with typical Becker muscular dystrophy. We conclude that the syndrome called quadriceps myopathy includes a group of forme fruste Becker muscular dystrophy.

We examined dystrophin, the protein product of the

    Duchenne muscular dystrophy gene
    DIAGNOSIS

, in

    muscle biopsy specimens
    PARACLINICAL

 from 4

    male
    GENDER

 patients with

    quadriceps myopathy
    DIAGNOSIS

, all of whom showed a

    mild and slowly progressive myopathy confined to the quadriceps muscles
    SYMPTOMS

. All 4 patients had

    clear abnormalities of dystrophin
    BIOCHEMICAL

, and were diagnosed as having

    Becker muscular dystrophy
    DIAGNOSIS

 by both

    immunofluorescence and immunoblot examinations
    PARACLINICAL

; that is,

    dystrophin of an abnormal molecular mass was visualized in muscle cryosections as "patchy" or discontinuous immunostaining at the surface membrane of the muscle fibers
    MICROSCOPIC

. One patient

    had a brother who showed widespread myopathic changes consistent with typical Becker muscular dystrophy
    FAMILY

. We conclude that the syndrome called

    quadriceps myopathy
    DIAGNOSIS

 includes a group of

    forme fruste Becker muscular dystrophy
    DIAGNOSIS

.

Duchenne muscular dystrophy gene
quadriceps myopathy
Becker muscular dystrophy
quadriceps myopathy
forme fruste Becker muscular dystrophy


Dystrophin protein and RFLP analysis for fetal diagnosis and carrier confirmation of Duchenne muscular dystrophy.

A pregnant woman with indeterminate Duchenne muscular dystrophy (DMD) carrier status, but with DMD diagnosed in her deceased brother (unavailable for study), presented for prenatal diagnosis, intending to continue the pregnancy only if proven unaffected with DMD with near absolute certainty. Creatine kinase (CK) assays to clarify carrier status were inconclusive. Male sex in the fetus was identified, but DNA restriction fragment length polymorphism (RFLP) analysis was not yet available to this centre to investigate the possible transmission of the DMD gene, and the pregnancy was terminated. Tissue histology and dystrophin protein analysis demonstrated the absence of DMD. In a situation with proven maternal carrier status, future fetal inheritance of the opposite maternal X chromosome would indicate the presence of DMD. However, maternal carrier status remained in doubt through a second pregnancy, even with RFLP studies, and was finally established when dystrophin analysis confirmed the presence of DMD in the second fetus. Histologic findings are presented, contrasting features in the two fetuses. The value of dystrophin analysis for establishing the diagnosis of fetal DMD, in this case proving maternal carrier status in a difficult situation, and for demonstrating DMD gene:RFLP haplotype relationships is illustrated.

A

    pregnant
    AGE

    woman
    GENDER

 with

    indeterminate Duchenne muscular dystrophy (DMD) carrier status
    NEG_FINDINGS

, but

    with DMD diagnosed in her deceased brother (unavailable
    FAMILY

 for study), presented for

    prenatal diagnosis
    PARACLINICAL

, intending to

    continue the pregnancy
    MEDICATION

 only if proven

    unaffected with DMD
    NEG_FINDINGS

 with near absolute certainty.

    Creatine kinase (CK) assays to clarify carrier status were inconclusive
    NEG_FINDINGS

.

    Male sex in the fetus
    SYMPTOMS

 was identified, but

    DNA restriction fragment length polymorphism (RFLP) analysis was not
    PARACLINICAL

 yet available to this centre to investigate the possible

    transmission of the DMD gene
    GENETICS

, and the

    pregnancy
    MEDICATION

 was terminated.

    Tissue histology
    PARACLINICAL

 and

    dystrophin protein analysis
    PARACLINICAL

 demonstrated the

    absence of DMD
    NEG_FINDINGS

. In a situation with

    proven maternal carrier status
    NEG_FINDINGS

,

    future fetal inheritance of the opposite maternal X chromosome
    FAMILY

 would indicate the presence

    of DMD
    FAMILY

. However,

    maternal carrier status remained in doubt through a second pregnancy, even with RFLP studies
    NEG_FINDINGS

, and was finally established when

    dystrophin analysis
    PARACLINICAL

 confirmed the

    presence of DMD in the second fetus
    SYMPTOMS

.

    Histologic findings
    PARACLINICAL

 are presented, contrasting features in the two fetuses. The value of

    dystrophin analysis
    PARACLINICAL

 for establishing the diagnosis of

    fetal DMD
    DIAGNOSIS

, in this case proving maternal carrier status in a difficult situation, and for demonstrating

    DMD gene:RFLP haplotype relationships
    GENETICS

 is illustrated.

Male sex in the fetus
presence of DMD in the second fetus

transmission of the DMD gene
DMD gene:RFLP haplotype relationships


[A case of severe infantile form of congenital nemaline myopathy with extensive fatty replacement of the skeletal muscles].

A case of severe infantile form of congenital nemaline myopathy who developed extensive fatty replacement of the skeletal muscles was described. A girl was born with severe hypotonia and flaccidity of the extremities. She was put on a ventilator because of the severe respiratory insufficiency. Muscle biopsy performed at 3 months of age revealed numerous nemaline rods in myofibers. She had an anoxic episode at 2 years of age and fell into a vegetative state after that. Serum creatine kinase and aldolase levels were normal. At 8 years of age, X-ray CT scan of the skeletal muscles revealed diffuse and severe fatty replacement of the skeletal muscles of the trunk and extremities; this was far more extensive than in the case of Duchenne muscular dystrophy of similar age. Second muscle biopsy performed in the anterior tibialis muscle at the age of 8 years revealed atrophic muscle fibers and extensive proliferation of connective and fatty tissues. Electron microscopy revealed, numerous rod-containing muscles fibers with severe disorganization and loss of myofilaments. Sural nerve biopsy performed at the same time showed decreased number of large myelinated fibers. Although a possibility could not be excluded completely that the episode of anoxia and chronic debilitation may have contributed to these pathological neuromuscular findings, it was presumed that severe degeneration and fatty replacement of the skeletal muscles progress rapidly after birth in some cases of severe infantile form of congenital nemaline myopathy.

A case of

    severe infantile form of congenital nemaline myopathy
    DIAGNOSIS

 who developed

    extensive fatty replacement of the skeletal muscles
    MICROSCOPIC

 was described. A

    girl
    GENDER

 was born with

    severe hypotonia
    SYMPTOMS

 and

    flaccidity of the extremities
    SYMPTOMS

.

    She
    GENDER

 was

    put on a ventilator
    MEDICATION

 because of the

    severe respiratory insufficiency
    SYMPTOMS

.

    Muscle biopsy
    PARACLINICAL

 performed

    at 3 months of age
    AGE

 revealed

    numerous nemaline rods in myofibers
    MICROSCOPIC

.

    She
    GENDER

 had an

    anoxic episode
    SYMPTOMS

    at 2 years of age
    AGE

 and

    fell into a vegetative state
    SYMPTOMS

 after that.

    Serum creatine kinase and aldolase levels were normal
    NEG_FINDINGS

. At

    8 years of age
    AGE

,

    X-ray CT scan of the skeletal muscles
    PARACLINICAL

 revealed

    diffuse and severe fatty replacement of the skeletal muscles of the trunk and extremities
    SYMPTOMS

; this was far more extensive than in the case of

    Duchenne muscular dystrophy
    DIAGNOSIS

 of

    similar age
    AGE

.

    Second muscle biopsy
    PARACLINICAL

 performed

    in the anterior tibialis muscle
    PARACLINICAL

 at the

    age of 8 years
    AGE

 revealed

    atrophic muscle fibers
    MICROSCOPIC

 and

    extensive proliferation of connective and fatty tissues
    MICROSCOPIC

.

    Electron microscopy
    PARACLINICAL

 revealed,

    numerous rod-containing muscles fibers with severe disorganization and loss of myofilaments
    MICROSCOPIC

.

    Sural nerve biopsy
    PARACLINICAL

 performed at the same time showed

    decreased number of large myelinated fibers
    SYMPTOMS

. Although a possibility could not be excluded completely that the episode of

    anoxia
    SYMPTOMS

 and

    chronic debilitation
    SYMPTOMS

 may have contributed to these

    pathological neuromuscular findings
    SYMPTOMS

, it was presumed that

    severe degeneration and fatty replacement of the skeletal muscles
    SYMPTOMS

 progress rapidly after

    birth
    AGE

 in some cases of

    severe infantile form of congenital nemaline myopathy
    DIAGNOSIS

.


Long-term observation of cardiac function in Duchenne's muscular dystrophy. Evaluation using systolic time intervals and echocardiography.

Cardiac involvement is common in patients with Duchenne type muscular dystrophy (DMD). However, published reports of long-term follow-up studies in the same patients are very rare. The purpose of this study was to clarify the natural course of cardiac dysfunction in DMD, and to analyze the relationship between the deterioration of cardiac function and skeletal muscular function. The cardiac function was serially evaluated for 2-12 years in 34 patients with DMD. The systolic time intervals and echocardiography were used for evaluating the cardiac function. The PEP/ET (pre-ejection period/ejection time) of systolic time intervals significantly deteriorated in 9-12 years (p less than 0.001). The maximal systolic and diastolic endocardial velocity (MSEV and MDEV) and the D/S ratio of echocardiography significantly deteriorated in 5 years (p less than 0.001). The D/S ratio is the ratio of the mean systolic velocity and the mean diastolic velocity of the left ventricular posterior wall. In almost half the patients, the deterioration of these parameters was correlated with that of Swinyard's stage. The Swinyard's functional ability stage demonstrates the grade of the skeletal muscular dysfunction. However, there was no correlation between the deterioration of cardiac function and Swinyard's stage in the other half of the patients. Correlation coefficient in the whole group was 0.32 (p = n.s.) between the PEP/ET and Swinyard's stage, and was -0.15 (p = n.s.) between the D/S ratio and Swinyard's stage. Although the mean left ventricular ejection fraction calculated using echocardiography was slightly decreased for 5 years, no significant change was detected in the whole group. One patient had progressive deterioration of left ventricular function despite mild skeletal muscular dysfunction, and died from congestive heart failure. The cardiac dysfunction was predominant. We named it 'cardiac type' DMD. Since deterioration of cardiac function was not always correlated with deterioration of skeletal muscular function (Swinyard's stage), cardiac function must be carefully monitored in patients with DMD.

    Cardiac involvement
    SYMPTOMS

 is common in patients with

    Duchenne type muscular dystrophy (DMD)
    DIAGNOSIS

. However, published reports of long-term follow-up studies in the same patients are very rare. The purpose of this study was to clarify the natural course of

    cardiac dysfunction
    SYMPTOMS

 in

    DMD
    DIAGNOSIS

, and to analyze the relationship between the

    deterioration of cardiac function
    SYMPTOMS

 and

    skeletal muscular function
    SYMPTOMS

. The

    cardiac function was serially evaluated for 2-12 years
    PARACLINICAL

 in 34 patients with

    DMD
    DIAGNOSIS

. The

    systolic time intervals
    PARACLINICAL

 and

    echocardiography
    PARACLINICAL

 were used for evaluating the

    cardiac function
    PARACLINICAL

. The PEP/ET (

    pre-ejection period/ejection time) of systolic time intervals significantly deteriorated
    SYMPTOMS

 in

    9-12 years
    AGE

 (p less than 0.001). The

    maximal systolic and diastolic endocardial velocity (MSEV and MDEV) and the D/S ratio of echocardiography significantly deteriorated
    SYMPTOMS

 in

    5 years
    AGE

 (p less than 0.001). The D/S ratio is the ratio of the mean

    systolic velocity and the mean diastolic velocity of the left ventricular posterior wall
    SYMPTOMS

. In almost half the patients, the

    deterioration of these parameters
    SYMPTOMS

 was correlated with that of

    Swinyard's stage
    SYMPTOMS

. The Swinyard's functional ability stage demonstrates the grade of the

    skeletal muscular dysfunction
    SYMPTOMS

. However, there was

    no correlation between
    NEG_FINDINGS

 the

    deterioration of cardiac function
    SYMPTOMS

    and Swinyard's stage
    NEG_FINDINGS

 in the other half of the patients. Correlation coefficient in the whole group was 0.32 (p = n.s.) between the

    PEP/ET
    PARACLINICAL

 and

    Swinyard's stage
    SYMPTOMS

, and was -0.15 (p = n.s.) between the D/S ratio and

    Swinyard's stage
    SYMPTOMS

. Although the

    mean left ventricular ejection fraction
    SYMPTOMS

 calculated using

    echocardiography
    PARACLINICAL

    was slightly decreased for 5 years
    SYMPTOMS

,

    no significant change
    NEG_FINDINGS

 was detected in the whole group. One patient had

    progressive deterioration of left ventricular function
    SYMPTOMS

    despite mild skeletal muscular dysfunction
    NEG_FINDINGS

, and

    died
    SYMPTOMS

 from

    congestive heart failure
    SYMPTOMS

. The

    cardiac dysfunction
    SYMPTOMS

 was predominant. We named it '

    cardiac type' DMD
    DIAGNOSIS

. Since

    deterioration of cardiac function
    SYMPTOMS

 was not always correlated with

    deterioration of skeletal muscular function (Swinyard's stage)
    SYMPTOMS

,

    cardiac function
    PARACLINICAL

 must be carefully monitored in patients with

    DMD
    DIAGNOSIS

.

Duchenne type muscular dystrophy (DMD)
DMD
DMD
cardiac type' DMD
DMD


[Two cases of X-linked ichthyosis associated with myopathies].

X-linked ichthyosis is an inborn error of metabolism due to the deficiency of steroid sulfatase. We reported two cases of the patients associated with myopathies, which are Duchenne muscular dystrophy (DMD) and myotonic dystrophy (MyD), respectively. In addition to DMD and MyD, they showed corneal opacities, lack of steroid-sulfatase activities in peripheral leukocytes and massive accumulation of cholesterol sulfate in plasma. Such cases were not reported, previously. Assay of steroid sulfatase and cholesterol sulfate in the patients having ichthyosis is important to elucidate the wide clinical spectrum of steroid sulfatase deficiency.

    X-linked
    GENETICS

    ichthyosis
    DIAGNOSIS

 is an

    inborn error of metabolism
    GENETICS

 due to the

    deficiency of steroid sulfatase
    BIOCHEMICAL

. We reported two cases of the patients associated with

    myopathies
    DIAGNOSIS

, which are

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

 and

    myotonic dystrophy (MyD)
    DIAGNOSIS

, respectively. In addition to

    DMD
    DIAGNOSIS

 and

    MyD
    DIAGNOSIS

, they showed

    corneal opacities
    SYMPTOMS

,

    lack of steroid-sulfatase activities in peripheral leukocytes
    BIOCHEMICAL

 and

    massive accumulation of cholesterol sulfate in plasma
    MICROSCOPIC

. Such cases were not reported, previously.

    Assay of steroid sulfatase and cholesterol sulfate
    PARACLINICAL

 in the patients having

    ichthyosis
    DIAGNOSIS

 is important to elucidate the wide clinical spectrum of

    steroid sulfatase deficiency
    BIOCHEMICAL

.

ichthyosis
myopathies
Duchenne muscular dystrophy (DMD)
myotonic dystrophy (MyD)
DMD
MyD
ichthyosis


Partial dystrophin deficiency in monozygous twin carriers of the Duchenne gene discordant for clinical myopathy.

We studied monozygous twin women, age 63. One, asymptomatic, had a serum creatine kinase (CK) level of 191 units (normal, 1 to 50); her son died of typical Duchenne muscular dystrophy (DMD) at age 18. Her twin sister had symptomatic limb weakness from about age 40. Her serum CK was 495 units. EMG and muscle biopsy were compatible with myopathy. In the asymptomatic twin, the peripheral blood lymphocyte karyotype was 46,XX. In the affected twin, 18% of cells were 45,X, and the others 46,XX, without X/autosome translocation. DNA analysis did not reveal a deletion at the DMD locus. Immunologic studies of dystrophin showed a partial deficiency of the protein that was more severe in the symptomatic twin. The clinical discordance and the different severity of dystrophin deficiency may have resulted from the effects of lyonization.

We studied

    monozygous twin women
    FAMILY

,

    age 63
    AGE

. One,

    asymptomatic
    NEG_FINDINGS

, had a

    serum creatine kinase (CK) level of 191 units (normal, 1 to 50)
    BIOCHEMICAL

;

    her
    GENDER

    son died of typical Duchenne muscular dystrophy (DMD)
    FAMILY

 at

    age 18
    AGE

.

    Her
    GENDER

    twin sister had symptomatic limb weakness
    FAMILY

    from about age 40
    AGE

.

    Her
    GENDER

    serum CK was 495 units
    BIOCHEMICAL

.

    EMG and muscle biopsy
    PARACLINICAL

 were compatible with

    myopathy
    DIAGNOSIS

. In the

    asymptomatic twin
    FAMILY

, the

    peripheral blood lymphocyte karyotype was 46,XX
    GENETICS

. In

    the affected twin
    FAMILY

,

    18% of cells were 45,X, and the others 46,XX, without X/autosome translocation
    GENETICS

.

    DNA analysis
    PARACLINICAL

    did not reveal a deletion at the DMD locus
    NEG_FINDINGS

.

    Immunologic studies of dystrophin
    PARACLINICAL

 showed a

    partial deficiency of the protein
    BIOCHEMICAL

    that was more severe in the symptomatic twin
    SYMPTOMS

. The

    clinical discordance
    SYMPTOMS

 and the different severity of

    dystrophin deficiency
    BIOCHEMICAL

 may have resulted from the effects of lyonization.


Dystrophin analysis in the differential diagnosis of autosomal recessive muscular dystrophy of childhood and Duchenne muscular dystrophy.

We report 2 patients with childhood autosomal recessive muscular dystrophy. Both patients had slight muscle weakness without enlargement of the calf muscles or involvement of the facial muscles. Their clinical courses are static. Muscle histology revealed characteristic features of muscular dystrophy. Dystrophin was identifiable in the sarcolemma of both patients by immunocytochemical staining with an antidystrophin antibody. At an early age, immunocytochemical analysis with antidystrophin antibody was useful in distinguishing between childhood autosomal recessive and Duchenne muscular dystrophies.

We report 2 patients with

    childhood autosomal recessive muscular dystrophy
    DIAGNOSIS

. Both patients had

    slight muscle weakness
    SYMPTOMS

    without enlargement of the calf muscles or involvement of the facial muscles
    NEG_FINDINGS

. Their clinical courses are static.

    Muscle histology
    PARACLINICAL

 revealed

    characteristic features of muscular dystrophy
    SYMPTOMS

.

    Dystrophin was identifiable in the sarcolemma
    MICROSCOPIC

 of both patients by

    immunocytochemical staining
    PARACLINICAL

 with an

    antidystrophin antibody
    BIOCHEMICAL

. At an

    early age
    AGE

,

    immunocytochemical analysis with antidystrophin antibody
    PARACLINICAL

 was useful in distinguishing between

    childhood autosomal recessive and Duchenne muscular dystrophies
    DIAGNOSIS

.


[Duchenne muscular dystrophy carrier presenting with mosaic X chromosome constitution and muscular symptoms--with analysis of the barr bodies in the muscle].

A 53-year-old female with muscular symptoms and incomplete Turner's syndrome was presented. She had two sons with Duchenne type muscular dystrophy (DMD). Her muscular symptoms became apparent at age 52 years, and her elevated serum CK, EMG and pathological findings of the biopsied muscle were consistent with muscular dystrophy. Her cytogenetic analysis from the cultured lymphocytes and fibroblasts showed a 45XO/46XX/47XXX chromosome constitution. Analysis of number of Barr bodies in the muscle specimen revealed that the total number of the bodies were significantly decreased in this case than in the control muscles. The result indicated that nuclei of 45XO karyotype were evidently present in her muscle and contributed to the process of muscle fiber breakdown as a major pathogenetic factor. However, inactivation of normal X chromosome also concerned the pathologic process because there were nuclei with Barr bodies in the damaged fibers as well. Only seven cases with X chromosome mosaicism and muscular symptoms attributable to DMD gene were seen in the literature. Four of them showed rather typical clinical features of DMD, but the muscular symptoms were much milder in the remainder, and patients were still able to walk in their middle lives. It was presumed that the severity of the clinical symptoms was parallel to the ratio of 45XO karyotype in the total number of muscular nuclei.

A

    53-year-old
    AGE

    female
    GENDER

 with

    muscular symptoms
    SYMPTOMS

 and

    incomplete Turner's syndrome
    DIAGNOSIS

 was presented.

    She
    GENDER

    had two sons with Duchenne type muscular dystrophy (DMD)
    FAMILY

.

    Her
    GENDER

    muscular symptoms
    SYMPTOMS

 became apparent at

    age 52 years
    AGE

, and

    her
    GENDER

    elevated serum CK
    BIOCHEMICAL

,

    EMG
    PARACLINICAL

 and

    pathological findings of the biopsied muscle
    PARACLINICAL

 were consistent with

    muscular dystrophy
    DIAGNOSIS

.

    Her
    GENDER

    cytogenetic analysis from the cultured lymphocytes and fibroblasts
    PARACLINICAL

 showed a

    45XO/46XX/47XXX chromosome constitution
    GENETICS

.

    Analysis of number of Barr bodies in the muscle specimen
    PARACLINICAL

 revealed that

    the total number of the bodies were significantly decreased in
    MICROSCOPIC

 this case

    than in the control muscles
    MICROSCOPIC

. The result indicated that

    nuclei of 45XO karyotype were evidently present in her muscle
    MICROSCOPIC

 and contributed to the process of

    muscle fiber breakdown
    MICROSCOPIC

 as a major pathogenetic factor. However,

    inactivation of normal X chromosome
    GENETICS

 also concerned the pathologic process because there were

    nuclei with Barr bodies in the damaged fibers as well
    MICROSCOPIC

. Only seven cases with

    X chromosome mosaicism
    GENETICS

 and

    muscular symptoms
    SYMPTOMS

 attributable to

    DMD gene
    DIAGNOSIS

 were seen in the literature. Four of them showed

    rather typical clinical features of DMD
    SYMPTOMS

, but the

    muscular symptoms
    SYMPTOMS

 were much milder in the remainder, and patients were still able to walk in their

    middle lives
    AGE

. It was presumed that the severity of the clinical symptoms was parallel to the

    ratio of 45XO karyotype in the total number of muscular nuclei
    GENETICS

.

muscular symptoms
muscular symptoms
muscular symptoms
rather typical clinical features of DMD
muscular symptoms

incomplete Turner's syndrome
muscular dystrophy
DMD gene


Analysis of Scottish Duchenne and Becker muscular dystrophy families with dystrophin cDNA probes.

One hundred and thirty-two Scottish families, representing the majority of currently known cases in this country with at least one living subject affected by DMD (110) or BMD (22), were studied with a series of cDNA probes excluding the 3' region of the gene (probes 10-14). Using mainly HindIII digested DNA from affected males, 89 patients showed deletions which ranged from 1 to 32 HindIII fragments in size. Two patients were also detected with exon duplications. Abnormalities were found to be particularly concentrated in the area of probe cDNA 8, with 56 patients being deleted for at least one of the fragments detected by this probe. A second smaller concentration of deletions was found with probe 1-2a which showed 16 deletions and two duplications. The endpoints of cDNA deletions or duplications were determined with a maximum variability of one HindIII fragment in 83 patients, while the remaining eight patients had a single deletion endpoint defined. The deletions found in two of our patients appear to conflict with the previously stated exon order at the 5' end of the gene. Although no specific deletion patterns were apparent for DMD, the deletions found in 13 of the BMD patients all included the most proximal (10 kb) fragment detected by probe 8.

One hundred and thirty-two

    Scottish
    ETHNICITY

 families, representing the majority of currently known cases in this country with at least one living subject affected by

    DMD
    DIAGNOSIS

 (110) or

    BMD
    DIAGNOSIS

 (22), were studied with a series of

    cDNA probes excluding the 3' region of the gene (probes 10-14)
    PARACLINICAL

. Using

    mainly HindIII digested DNA
    PARACLINICAL

 from affected

    males
    GENDER

, 89 patients showed

    deletions which ranged from 1 to 32 HindIII fragments in size
    GENETICS

. Two patients were also detected with

    exon duplications
    GENETICS

. Abnormalities were found to be particularly concentrated in the area of

    probe cDNA 8
    GENETICS

, with 56 patients being

    deleted for at least one of the fragments detected
    GENETICS

 by this probe. A second smaller concentration of deletions was found with

    probe 1-2a
    PARACLINICAL

 which showed 16 deletions and two

    duplications
    GENETICS

. The endpoints of

    cDNA deletions or duplications
    GENETICS

 were determined with a maximum variability of one HindIII fragment in 83 patients, while the remaining eight patients had a single deletion endpoint defined. The deletions found in two of our patients appear to

    conflict with the previously stated exon order at the 5' end of the gene
    GENETICS

. Although no specific deletion patterns were apparent for

    DMD
    DIAGNOSIS

, the deletions found in 13 of the

    BMD
    DIAGNOSIS

 patients all included

    the most proximal (10 kb) fragment
    GENETICS

 detected by probe 8.


Aland Island eye disease (Forsius-Eriksson ocular albinism) and an Xp21 deletion in a patient with Duchenne muscular dystrophy, glycerol kinase deficiency, and congenital adrenal hypoplasia.

Glycerol kinase deficiency (GKD) has been described in isolation and in complex phenotypes including either congenital adrenal hypoplasia, Duchenne muscular dystrophy, or both. Cytogenetic and molecular studies have localized these defects to a deletion involving the X chromosome at band Xp21, consistent with its X-linked recessive pattern of inheritance. Other clinical findings in the complex glycerol kinase deficiency (CGKD) patients are mental retardation, short stature, and hypogonadotropic hypogonadism. We report on a 6-year-old boy who, in addition to the CGKD phenotype described above, had ocular hypopigmentation consistent with Forsius-Eriksson ocular albinism, also known as type 2 ocular albinism or Aland Island eye disease. Cytogenetic analysis shows an interstitial deletion in the short arm of the X-chromosome at Xp21.

    Glycerol kinase deficiency (GKD)
    DIAGNOSIS

 has been described in isolation and in complex phenotypes including either

    congenital adrenal hypoplasia
    DIAGNOSIS

,

    Duchenne muscular dystrophy
    DIAGNOSIS

, or both.

    Cytogenetic and molecular studies
    PARACLINICAL

 have localized these defects to a

    deletion involving the X chromosome at band Xp21
    GENETICS

, consistent with its

    X-linked recessive pattern of inheritance
    GENETICS

. Other clinical findings in the

    complex glycerol kinase deficiency (CGKD)
    DIAGNOSIS

 patients are

    mental retardation
    SYMPTOMS

,

    short stature
    SYMPTOMS

, and

    hypogonadotropic hypogonadism
    SYMPTOMS

. We report on a

    6-year-old
    AGE

    boy
    GENDER

 who, in addition to the

    CGKD phenotype
    SYMPTOMS

 described above, had

    ocular hypopigmentation consistent with Forsius-Eriksson ocular albinism
    SYMPTOMS

, also known as

    type 2 ocular albinism
    DIAGNOSIS

 or

    Aland Island eye disease
    DIAGNOSIS

.

    Cytogenetic analysis
    PARACLINICAL

 shows an

    interstitial deletion in the short arm of the X-chromosome at Xp21.
    GENETICS


[A female infant of mitochondrial myopathy with findings of active necrosis and regeneration of muscle fibers].

An 8 year-old female infant with the clinical and pathological characteristics of both progressive muscular dystrophy and mitochondrial myopathy was described. Her maternal cousin had clinical and pathological findings of Duchenne muscular dystrophy (DMD). Since the patient had markedly elevated serum CK and calf muscle hypertrophy, her muscle was biopsied and she was diagnosed as having female DMD at the age of 5 years. She had generalized tonic-clonic convulsions and alternate hemiconvulsions for recent 4 years which brought her our hospital. On admission, she had mild generalized muscle atrophy and weakness predominantly in the proximal limbs. The lactate and pyruvate levels in both serum and cerebrospinal fluid were elevated, but with no metabolic acidosis. Serum CK was elevated to 4464 IU/L. Brain CT and MRI showed the expanding arachnoid cyst in the left middle fossa of cranium. In the biopsied left biceps crachii muscle, in addition to numerous ragged-red fibers, there were active muscular fiber necrosis and regeneration and interstitial fibrosis similar to those seen in progressive muscular dystrophy. Biochemically, no decrease or defect in the respiratory chain enzymes was detected. On electron microscopy, a large number of fibers contained aggregates of giant mitochondria with proliferated complicated cristae. Scattered throughout were necrotic muscle fibers filled with phagocytes and regenerating fibers. This patient had the diagnostic features of mitochondrial encephalomyopathy and progressive muscular dystrophy. We supposed that the patient provided very interesting evidences to study the relationship between mitochondrial myopathy and progressive muscular dystrophy.

An

    8 year-old
    AGE

    female
    GENDER

    infant
    AGE

 with the

    clinical and pathological characteristics of both progressive muscular dystrophy
    SYMPTOMS

 and

    mitochondrial myopathy
    DIAGNOSIS

 was described.

    Her
    GENDER

    maternal cousin had clinical and pathological findings of Duchenne muscular dystrophy (DMD)
    FAMILY

. Since the patient had

    markedly elevated serum CK
    BIOCHEMICAL

 and

    calf muscle hypertrophy
    SYMPTOMS

,

    her
    GENDER

    muscle was biopsied
    PARACLINICAL

 and

    she
    GENDER

 was diagnosed as having

    female DMD
    DIAGNOSIS

 at the

    age of 5 years
    AGE

.

    She
    GENDER

 had

    generalized tonic-clonic convulsions
    SYMPTOMS

 and

    alternate hemiconvulsions
    SYMPTOMS

 for

    recent 4 years
    SYMPTOMS

 which brought

    her
    GENDER

 our hospital. On admission,

    she
    GENDER

 had

    mild generalized muscle atrophy
    SYMPTOMS

 and

    weakness predominantly in the proximal limbs
    SYMPTOMS

.

    The lactate and pyruvate levels in both serum and cerebrospinal fluid were elevated
    BIOCHEMICAL

, but

    with no metabolic acidosis
    NEG_FINDINGS

. Serum CK was elevated to 4464 IU/L.

    Brain CT
    PARACLINICAL

 and

    MRI
    PARACLINICAL

 showed the

    expanding arachnoid cyst in the left middle fossa of cranium
    SYMPTOMS

. In the

    biopsied left biceps crachii muscle
    PARACLINICAL

, in addition to

    numerous ragged-red fibers
    MICROSCOPIC

, there were

    active muscular fiber necrosis and regeneration
    MICROSCOPIC

 and

    interstitial fibrosis
    MICROSCOPIC

    similar to those seen in progressive muscular dystrophy
    MICROSCOPIC

. Biochemically,

    no decrease or defect in the respiratory chain enzymes was detected
    NEG_FINDINGS

. On

    electron microscopy
    PARACLINICAL

, a

    large number of fibers contained aggregates of giant mitochondria with proliferated complicated cristae
    MICROSCOPIC

.

    Scattered throughout were necrotic muscle fibers filled with phagocytes and regenerating fibers
    MICROSCOPIC

. This patient had the diagnostic features of

    mitochondrial encephalomyopathy
    DIAGNOSIS

 and

    progressive muscular dystrophy
    DIAGNOSIS

. We supposed that the patient provided very interesting evidences to study the relationship between

    mitochondrial myopathy
    DIAGNOSIS

 and

    progressive muscular dystrophy
    DIAGNOSIS

.

mitochondrial myopathy
female DMD
mitochondrial encephalomyopathy
progressive muscular dystrophy
mitochondrial myopathy
progressive muscular dystrophy


Skewed X inactivation in a female MZ twin results in Duchenne muscular dystrophy.

One of female MZ twins presented with muscular dystrophy. Physical examination, creatine phosphokinase levels, and muscle biopsy were consistent with Duchenne muscular dystrophy (DMD). However, because of her sex she was diagnosed as having limb-girdle muscular dystrophy. With cDNA probes to the DMD gene, a gene deletion was detected in the twins and their mother. The de novo mutation which arose in the mother was shown by novel junction fragments generated by HindIII, PstI, or TaqI when probed with cDNA8. Additional evidence of a large gene deletion was given by novel SfiI junction fragments detected by probes p20, J-Bir, and J-66 on pulsed-field gel electrophoresis (PFGE). Immunoblot analysis of muscle from the affected twin showed dystrophin of normal size but of reduced amount. Immunofluorescent visualization of dystrophin revealed foci of dystrophin-positive fibers adjacent to foci of dystrophin-negative fibers. These data indicate that the affected twin is a manifesting carrier of an abnormal DMD gene, her myopathy being a direct result of underexpression of dystrophin. Cytogenetic analysis revealed normal karyotypes, eliminating the possibility of a translocation affecting DMD gene function. Both linkage analysis and DNA fingerprint analysis revealed that each twin has two different X chromosomes, eliminating the possibility of uniparental disomy as a mechanism for DMD expression. On the basis of methylation differences of the paternal and maternal X chromosomes in these MZ twins, we propose uneven lyonization (X chromosome inactivation) as the underlying mechanism for disease expression in the affected female.

One of

    female
    GENDER

    MZ twins
    FAMILY

 presented with

    muscular dystrophy
    DIAGNOSIS

.

    Physical examination
    PARACLINICAL

,

    creatine phosphokinase levels
    BIOCHEMICAL

, and

    muscle biopsy
    PARACLINICAL

 were consistent with

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

. However, because of

    her
    GENDER

 sex

    she
    GENDER

 was diagnosed as having

    limb-girdle muscular dystrophy
    DIAGNOSIS

. With

    cDNA probes to the DMD gene
    PARACLINICAL

, a

    gene deletion was detected in the twins and their mother
    FAMILY

. The

    de novo mutation which arose in the mother
    GENETICS

 was shown by novel junction fragments generated by HindIII, PstI, or

    TaqI
    GENETICS

 when probed

    with cDNA8
    PARACLINICAL

. Additional evidence of a

    large gene deletion
    GENETICS

 was given by

    novel SfiI junction fragments
    GENETICS

 detected by probes p20, J-Bir, and J-66 on

    pulsed-field gel electrophoresis (PFGE)
    PARACLINICAL

.

    Immunoblot analysis of muscle from the affected twin
    PARACLINICAL

 showed

    dystrophin of normal size but of reduced amount
    BIOCHEMICAL

.

    Immunofluorescent visualization of dystrophin
    PARACLINICAL

 revealed

    foci of dystrophin-positive fibers adjacent to foci of dystrophin-negative fibers
    MICROSCOPIC

. These data indicate that the

    affected twin is a manifesting carrier of an abnormal DMD gene
    FAMILY

,

    her
    GENDER

    myopathy
    SYMPTOMS

 being a direct result of

    underexpression of dystrophin
    BIOCHEMICAL

.

    Cytogenetic analysis
    PARACLINICAL

 revealed

    normal karyotypes
    NEG_FINDINGS

,

    eliminating the possibility of a translocation affecting DMD gene function
    NEG_FINDINGS

. Both

    linkage analysis
    PARACLINICAL

 and

    DNA fingerprint analysis
    PARACLINICAL

 revealed that

    each twin has two different X chromosomes
    FAMILY

,

    eliminating the possibility of uniparental disomy as a mechanism for DMD expression
    NEG_FINDINGS

. On the basis of

    methylation differences of the paternal and maternal X chromosomes in these MZ twins
    GENETICS

, we propose

    uneven lyonization (X chromosome inactivation)
    GENETICS

 as the underlying mechanism for disease expression in the affected

    female
    GENDER

.

muscular dystrophy
Duchenne muscular dystrophy (DMD)
limb-girdle muscular dystrophy


Genetic counselling in Duchenne and Becker muscular dystrophy is problematic when carrier studies give controversial results.

DNA-analysis with flanking and intragenic markers gave confusing results in 7 out of 74 (9.5%) Finnish families with Duchenne or Becker muscular dystrophy. In five families a sister or maternal aunt of the patient had elevated serum creatine kinase (CK) activity, although DNA-analysis indicated a low risk for carriership. In one family the two affected brothers had different pERT87 alleles. In one family the intragenic deletion found in a patient was not present in his mother, who was an obligatory carrier. Deletions were detected with cDNA probes in the probands in five of the families, but the controversy regarding carriership still remained. It is necessary to combine all available data from pedigree analysis, CK measurements, and DNA studies whenever carrier studies are performed, but it appears that major problems in counselling and prenatal diagnosis will still remain in a proportion of the families.

    DNA-analysis with flanking and intragenic markers
    PARACLINICAL

 gave confusing results in 7 out of 74 (9.5%)

    Finnish
    ETHNICITY

 families with

    Duchenne or Becker muscular dystrophy
    DIAGNOSIS

. In five families

    a sister or maternal aunt of the patient had elevated serum creatine kinase (CK) activity
    FAMILY

, although

    DNA-analysis
    PARACLINICAL

 indicated a

    low risk for carriership
    FAMILY

. In one family

    the two affected brothers had different pERT87 alleles
    FAMILY

. In one family

    the intragenic deletion found in a patient was not present in his mother, who was an obligatory carrier
    FAMILY

. Deletions were detected with

    cDNA probes
    PARACLINICAL

 in the probands in five of the families, but the controversy regarding carriership still remained. It is necessary to combine all available data from

    pedigree analysis
    PARACLINICAL

,

    CK measurements
    PARACLINICAL

, and

    DNA studies
    PARACLINICAL

 whenever

    carrier studies
    PARACLINICAL

 are performed, but it appears that major problems in counselling and

    prenatal diagnosis
    PARACLINICAL

 will still remain in a proportion of the families.


[Prenatal diagnosis of Duchenne muscular dystrophy by fetoscopic muscle biopsy. Report of a case].

A needle muscle biopsy through a fetoscope for the antenatal diagnosis of Duchenne muscular dystrophy (DMD) was reported the mother was a carrier of 30 years old with a family history of Duchenne muscular dystrophy. Her brother died of DMD and her son had suffering from DMD. At 17 weeks of her second gestation, an amniotic puncture was performed. The cellular chromosome was found to be a male fetus (46,xy). At 20 weeks of her gestation, a needle muscle biopsy of the male fetus was performed under fetoscopy and turned out to be Duchenne muscular dystrophy. At 23 weeks, a male fetus was born with induced labor. The pre and postnatal muscles were examined under the light and electron--microscopes. The large hyaline round fibres were positive for calcium. There was evidence of a break down of the basement membranes, appearance of A and I bands and fragmentation of Z bands. Myofibrils were replaced by thin filaments. The diagnosis of Duchenne muscular dystrophy was established on the basic of these findings. This was considered the first case of antenatal fetal Duchenne muscular dystrophy diagnosed with the aid of fetoscope and needle muscle biopsy.

A

    needle muscle biopsy through a fetoscope
    PARACLINICAL

 for the

    antenatal
    AGE

 diagnosis of

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

 was reported the

    mother
    GENDER

 was a

    carrier of 30 years old
    FAMILY

    with a family history of Duchenne muscular dystrophy
    FAMILY

.

    Her
    GENDER

    brother died of DMD
    FAMILY

 and

    her
    GENDER

    son had suffering from DMD
    FAMILY

. At

    17 weeks of her second gestation
    MEDICATION

, an

    amniotic puncture
    PARACLINICAL

 was performed. The cellular chromosome was found to be a

    male fetus (46,xy)
    GENETICS

. At

    20 weeks of her gestation
    AGE

, a

    needle muscle biopsy of the male fetus
    PARACLINICAL

 was performed under

    fetoscopy
    PARACLINICAL

 and turned out to be

    Duchenne muscular dystrophy
    DIAGNOSIS

.

    At 23 weeks
    AGE

, a

    male
    GENDER

    fetus
    AGE

 was born with

    induced labor
    MEDICATION

.

    The pre and postnatal muscles
    PARACLINICAL

 were examined under the

    light and electron--microscopes
    PARACLINICAL

. The

    large hyaline round fibres were positive for calcium
    MICROSCOPIC

. There was evidence of a

    break down of the basement membranes
    MICROSCOPIC

,

    appearance of A and I bands
    SYMPTOMS

 and

    fragmentation of Z bands
    MICROSCOPIC

.

    Myofibrils were replaced by thin filaments
    MICROSCOPIC

. The diagnosis of

    Duchenne muscular dystrophy
    DIAGNOSIS

 was established on the basic of these findings. This was considered the first case of

    antenatal fetal Duchenne muscular dystrophy
    DIAGNOSIS

 diagnosed with the aid of

    fetoscope
    PARACLINICAL

 and

    needle muscle biopsy
    PARACLINICAL

.

17 weeks of her second gestation
induced labor


Very mild muscular dystrophy associated with the deletion of 46% of dystrophin.

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD), a much milder form of the disease where the age of onset can sometimes be as late as the third or fourth decade of life, are caused by mutations in the same X-linked gene, a 14 kilobase (kb) transcript which is spread over more than 2 megabases of the human X chromosome. The corresponding protein, dystrophin, has a relative molecular mass of 400,000. Most mutations causing DMD and BMD are deletions and deletions associated with both phenotypes are observed throughout the gene sequence. This observation led to the suggestion that DMD patients possess deletions that disrupt the reading frame of the protein, whereas BMD patients have deletions that retain the translational reading frame and enable the muscle cells to produce altered dystrophin products. This theory is supported by immunoblotting studies, which show that DMD patients lack dystrophin in their muscle cells or that dystrophin is present at very low levels, whereas BMD patients produce a protein with reduced abundance or abnormal size. Here we describe a deletion of the dystrophin gene in a family segregating for very mild BMD, one member of which was still ambulant at age 61 years, which removes a central part of the dystrophin gene encompassing 5,106 base pairs of coding sequence, almost half the coding information. Immunological analysis of muscle from one of the patients demonstrates that this mutation results in the production of a truncated polypeptide localized correctly in the muscle cell. These results are particularly significant in the context of gene therapy which, if it is ever envisaged, would be facilitated by the replacement of the very large dystrophin gene with a more manipulatable mini-gene construct.

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

 and

    Becker muscular dystrophy (BMD)
    DIAGNOSIS

, a much milder form of the disease where the age of onset can sometimes be as late as

    the third or fourth decade of life
    AGE

, are caused by

    mutations in the same X-linked gene, a 14 kilobase (kb) transcript which is spread over more than 2 megabases of the human X chromosome
    GENETICS

. The corresponding protein, dystrophin, has a relative molecular mass of 400,000. Most mutations causing

    DMD
    DIAGNOSIS

 and

    BMD
    DIAGNOSIS

 are

    deletions and deletions associated with both phenotypes are observed throughout the gene sequence
    GENETICS

. This observation led to the suggestion that

    DMD
    DIAGNOSIS

 patients possess

    deletions that disrupt the reading frame of the protein
    GENETICS

, whereas

    BMD
    DIAGNOSIS

 patients have

    deletions that retain the translational reading frame
    GENETICS

 and enable the muscle cells to produce altered dystrophin products. This theory is supported by

    immunoblotting studies
    PARACLINICAL

, which show that

    DMD
    DIAGNOSIS

 patients

    lack dystrophin in their muscle cells
    MICROSCOPIC

 or that

    dystrophin is present at very low levels
    BIOCHEMICAL

, whereas

    BMD
    DIAGNOSIS

 patients produce a

    protein with reduced abundance or abnormal size
    BIOCHEMICAL

. Here we describe a

    deletion of the dystrophin gene
    GENETICS

 in a

    family segregating for very mild BMD, one member of which was still ambulant
    FAMILY

    at age 61 years
    AGE

, which

    removes a central part of the dystrophin gene encompassing 5,106 base pairs of coding sequence, almost half the coding information
    GENETICS

.

    Immunological analysis of muscle
    PARACLINICAL

 from one of the patients demonstrates that this mutation results in the production of a

    truncated polypeptide localized correctly in the muscle cell
    BIOCHEMICAL

. These results are particularly significant in the context of

    gene therapy
    MEDICATION

 which, if it is ever envisaged, would be facilitated by the

    replacement of the very large dystrophin gene
    MEDICATION

 with a more

    manipulatable mini-gene construct
    MEDICATION

.

Duchenne muscular dystrophy (DMD)
Becker muscular dystrophy (BMD)
DMD
BMD
DMD
BMD
DMD
BMD


[A manifesting carrier of Duchenne muscular dystrophy presenting mosaic distribution of dystrophin negative and positive muscle fibers].

A 25-year-old female patient with an approximate 10-year-history of slowly progressive muscle weakness was diagnosed as a manifesting carrier of Duchenne muscular dystrophy (DMD) because her muscle biopsy showed scattered fibers with no dystrophin on immunohistochemical staining. She had no family history of neuromuscular disorders. She was in good health until about 14 years of age, when she developed muscle weakness and atrophy of the extremities with slow aggravation. On admission at the age of 25 years, she had asymmetrical muscle atrophy in the lower extremities; the left femur, right femur, left crus, and right crus measured 36.0, 40.5, 31.5, and 35.5 cm in circumference, respectively. However, the muscle weakness of the extremities was symmetrical with no laterality, and the proximal muscles in the lower extremities were predominantly affected to 3+/5 MMT test. She walked with a mild wadding manner and stood up with Gower' maneuver. Deep tendon reflexes of the extremities were almost normoactive with no pathologic reflexes. As to laboratory findings, serum enzymes of muscular origin were elevated; GOT was 44 IU/l, GPT 60 IU/l, LDH 829 IU/l, CK 4238 IU/l, and aldolase 31 SL units. The electromyogram showed myopathic changes mixed with some neurogenic components. Peripheral nerve conduction velocity was normal. A computed tomography of the skeletal muscles showed more marked atrophy and lower density in the left lower extremity than in the right. The biopsied left gastrocnemius muscle demonstrated a marked variation in fiber size with some necrotic and regenerating fibers. On immunohistochemical stain with anti-dystrophin antibody, the dystrophin negative fibers were scattered among positive fibers in a mosaic distribution.

A

    25-year-old
    AGE

    female
    GENDER

 patient with an approximate 10-year-history of

    slowly progressive muscle weakness
    SYMPTOMS

 was diagnosed as a manifesting carrier of

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

 because

    her
    GENDER

    muscle biopsy
    PARACLINICAL

 showed

    scattered fibers with no dystrophin
    MICROSCOPIC

 on

    immunohistochemical staining
    PARACLINICAL

.

    She
    GENDER

 had

    no family history of neuromuscular disorders
    NEG_FINDINGS

.

    She
    GENDER

 was in good health until

    about 14 years of age
    AGE

, when

    she
    GENDER

 developed

    muscle weakness and atrophy of the extremities with slow aggravation
    SYMPTOMS

. On admission at the

    age of 25 years
    AGE

,

    she
    GENDER

 had

    asymmetrical muscle atrophy in the lower extremities; the left femur, right femur, left crus, and right crus measured 36.0, 40.5, 31.5, and 35.5 cm in circumference, respectively
    SYMPTOMS

. However, the

    muscle weakness of the extremities was symmetrical with no laterality
    SYMPTOMS

, and

    the proximal muscles in the lower extremities were predominantly affected to 3+/5 MMT test
    SYMPTOMS

.

    She
    GENDER

    walked with a mild wadding manner and stood up with Gower' maneuver
    SYMPTOMS

.

    Deep tendon reflexes of the extremities were almost normoactive with no pathologic reflexes
    NEG_FINDINGS

. As to

    laboratory findings
    PARACLINICAL

,

    serum enzymes of muscular origin
    BIOCHEMICAL

    were elevated
    BIOCHEMICAL

;

    GOT was 44 IU/l, GPT 60 IU/l, LDH 829 IU/l, CK 4238 IU/l, and aldolase 31 SL units
    BIOCHEMICAL

. The

    electromyogram
    PARACLINICAL

 showed

    myopathic changes mixed with some neurogenic components
    SYMPTOMS

.

    Peripheral nerve conduction velocity was normal
    NEG_FINDINGS

. A

    computed tomography of the skeletal muscles
    PARACLINICAL

 showed

    more marked atrophy and lower density in the left lower extremity than in the right
    SYMPTOMS

. The

    biopsied left gastrocnemius muscle
    PARACLINICAL

 demonstrated a

    marked variation in fiber size with some necrotic and regenerating fibers
    MICROSCOPIC

. On

    immunohistochemical stain with anti-dystrophin antibody
    PARACLINICAL

,

    the dystrophin negative fibers were scattered among positive fibers in a mosaic distribution
    MICROSCOPIC

.


Mosaic pattern of dystrophins in Duchenne muscular dystrophy.

Dystrophin is the gene product affected in Duchenne muscular dystrophy (DMD). Dystrophin is demonstrably absent with immunocytochemical staining and undetectable by western blotting of DMD muscles. We report an isolated 7-year-old girl with DMD. Analysis of the patient's and her mother's DNA, with probes covering the DMD gene, disclosed no deletion. We have studied dystrophin in biopsied muscle from the patient using antidystrophin antibody in combination with immunofluorescence. Random presence of normal and dystrophin-deficient fibers were indicative of mosaic expression. Dystrophin immunocytochemistry may be useful for accurate diagnosis of affected females.

Dystrophin is the gene product affected in

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

. Dystrophin is demonstrably absent with

    immunocytochemical staining
    PARACLINICAL

 and

    undetectable
    NEG_FINDINGS

 by

    western blotting
    PARACLINICAL

 of

    DMD muscles
    NEG_FINDINGS

. We report an isolated

    7-year-old
    AGE

    girl
    GENDER

 with

    DMD
    DIAGNOSIS

.

    Analysis of the patient's and her mother's DNA, with probes covering the DMD gene
    PARACLINICAL

, disclosed

    no deletion
    GENETICS

. We have

    studied dystrophin in biopsied muscle
    PARACLINICAL

 from the patient using

    antidystrophin antibody
    PARACLINICAL

 in combination with

    immunofluorescence
    PARACLINICAL

.

    Random presence of normal and dystrophin-deficient fibers
    MICROSCOPIC

 were indicative of

    mosaic expression
    MICROSCOPIC

.

    Dystrophin immunocytochemistry
    PARACLINICAL

 may be useful for accurate diagnosis of affected

    females
    GENDER

.


[Developmental disorders in young children with Duchenne's muscular dystrophy: implications for diagnosis and treatment].

The article describes two toddlers having Duchenne muscular dystrophy. In addition to motor problems they also exhibit attention disorders, deficits in short-term memory, speech and language disorders, and poor achievement motivation. Similar problems are reported in older Duchenne children. The etiology of the developmental disabilities, the content of the assessment protocol and the necessity for early intervention are discussed.

The article describes two

    toddlers
    AGE

 having

    Duchenne muscular dystrophy
    DIAGNOSIS

. In addition to

    motor problems
    SYMPTOMS

 they also exhibit

    attention disorders
    SYMPTOMS

,

    deficits in short-term memory
    SYMPTOMS

,

    speech and language disorders
    SYMPTOMS

, and

    poor achievement motivation
    SYMPTOMS

. Similar problems are reported in

    older
    AGE

    Duchenne
    DIAGNOSIS

    children
    AGE

. The etiology of the

    developmental disabilities
    SYMPTOMS

, the content of the assessment protocol and the necessity for

    early intervention
    MEDICATION

 are discussed.

motor problems
attention disorders
deficits in short-term memory
speech and language disorders
poor achievement motivation
developmental disabilities


Dystrophin analysis in the diagnosis of muscular dystrophy.

We present a family in which the differential diagnosis between X linked Duchenne muscular dystrophy and autosomal recessive Duchenne-like muscular dystrophy was resolved in favour of the latter by analysis of dystrophin, which is the protein product of the Duchenne muscular dystrophy locus.

We present a family in which the

    differential diagnosis
    PARACLINICAL

 between

    X linked Duchenne muscular dystrophy
    DIAGNOSIS

 and

    autosomal recessive Duchenne-like muscular dystrophy
    DIAGNOSIS

 was resolved in favour of the latter by

    analysis of dystrophin
    PARACLINICAL

, which is the

    protein product of the Duchenne muscular dystrophy locus
    GENETICS

.


Duchenne muscular dystrophy in Wales: impact of DNA linkage analysis and cDNA deletion screening.

A register of families with Duchenne muscular dystrophy (DMD) has been maintained in Wales since 1973. Since 1986 we have attempted to refine carrier status, and when necessary offer prenatal diagnosis, for those at significant risk by using intragenic probes. cDNA probes were included from the beginning of 1988. Thirty-four (30%) of the 115 women tested were assigned a risk of carrying the DMD gene of less than 5%. Thirty-three (29%) of the women at 5% or greater risk are now able to have prenatal diagnosis using a molecular deletion; such deletions were detected in 50% of affected boys. The remaining women could have prenatal diagnosis using a linked intragenic probe with an error rate varying between 0.25% and 9%. In 19 cases DNA samples from DMD boys who were dead at the time of analysis were used, indicating that it is essential to bank DNA from all males affected by DMD. We conclude that a large proportion of women at risk of carrying the DMD gene can now be helped by DNA studies.

A register of families with

    Duchenne muscular dystrophy (DMD)
    DIAGNOSIS

 has been maintained in

    Wales
    ETHNICITY

 since 1973. Since 1986 we have attempted to refine carrier status, and when necessary offer

    prenatal diagnosis
    MEDICATION

, for those at significant risk by using

    intragenic probes
    PARACLINICAL

.

    cDNA probes
    MEDICATION

 were included from the beginning of 1988. Thirty-four (30%) of the 115

    women
    GENDER

 tested were assigned a risk

    of carrying the DMD gene of less than 5%
    FAMILY

. Thirty-three (29%) of the

    women
    GENDER

 at 5% or greater risk are now able to have

    prenatal diagnosis
    PARACLINICAL

 using a

    molecular deletion
    PARACLINICAL

; such deletions were detected in 50% of affected

    boys
    GENDER

. The remaining

    women
    GENDER

 could have

    prenatal diagnosis
    PARACLINICAL

 using a

    linked intragenic probe
    PARACLINICAL

 with an error rate varying between 0.25% and 9%. In 19 cases DNA samples from

    DMD
    AGE

    boys
    GENDER

 who were dead at the time of analysis were used, indicating that it is essential to bank DNA from all

    males
    GENDER

 affected by

    DMD
    DIAGNOSIS

. We conclude that a large proportion of

    women
    GENDER

 at risk of

    carrying the DMD gene
    GENETICS

 can now be helped by

    DNA studies
    PARACLINICAL

.