Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rigid spine syndrome is a term first proposed by Dubowitz to describe a subset of patients affected by myopathy with early spinal contractures as a prominent feature. While spinal rigidity is a nonspecific feature, found in Emery-Dreifuss muscular dystrophy and in some congenital myopathies, it is also a prominent feature in a group of patients with merosin-positive congenital muscular dystrophy, where it is generally associated with stable or only slowly progressive weakness and early respiratory insufficiency. Recently, the first locus for congenital muscular dystrophy in association with rigid spine syndrome was mapped to chromosome 1p35-p36 in consanguineous Moroccan, Turkish, and Iranian families. We present here a detailed phenotypic description of the familial syndrome linked to this locus, describing 4 siblings (3 boys and 1 girl) of Northern European-American heritage who are the offspring of a nonconsanguineous marriage. All 4 siblings were affected by hypotonia and prominent neck weakness in infancy, early spinal rigidity, and early scoliosis. After initial improvement, muscle strength stabilizes or slowly declines, and skeletal deformities and respiratory insufficiency supervene. Muscle biopsy in an affected child at age 9 months revealed minimal, nonspecific myopathic changes, leading to a diagnosis of "minimal change myopathy." Muscle biopsy in his sibling, at the age of 14 years, revealed chronic and severe myopathic (dystrophic) changes, with normal staining for laminin-2 and for proteins of the dystrophin-glycoprotein complex. A possible explanation for these biopsy findings is that magnetic resonance imaging of the thighs reveals stereotyped selective muscle involvement, with the selectivity more pronounced early in the disease course followed by widespread muscular signal abnormalities in the late stages of the disease. In this family, linkage to the chromosome 1p rigid spine syndrome locus (RSMD1) is supported by maximum LOD scores for several markers of 1.81 at theta = 0, representing the maximum statistical power possible for this family. In combination with the previous report, this syndrome is linked to the RSMD1 locus with a summated maximum LOD score of 6.29, and analysis of recombination events in our family narrows the previously reported RSMD1 locus to 3 centiMorgans.
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PMID:Congenital muscular dystrophy with rigid spine syndrome: a clinical, pathological, radiological, and genetic study. 1066 83

One form of congenital muscular dystrophy, rigid spine syndrome (MIM 602771), is a rare neuromuscular disorder characterized by early rigidity of the spine and respiratory insufficiency. A locus on 1p35-36 (RSMD1) was recently found to segregate with rigid spine muscular dystrophy 1 (ref. 1). Here we refine the locus and find evidence of linkage disequilibrium associated with SEPN1, which encodes the recently described selenoprotein N (ref. 2). Our identification and analysis of mutations in SEPN1 is the first description of a selenoprotein implicated in a human disease.
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PMID:Mutations in SEPN1 cause congenital muscular dystrophy with spinal rigidity and restrictive respiratory syndrome. 1152 83

Multiminicore disease (MmD) is an autosomal recessive congenital myopathy characterized by the presence of multiple, short core lesions (known as "minicores") in most muscle fibers. MmD is a clinically heterogeneous condition, in which four subgroups have been distinguished. Homozygous RYR1 mutations have been recently identified in the moderate form of MmD with hand involvement. The genes responsible for the three other forms (including the most prevalent phenotype, termed the "classical" phenotype) remained, so far, unknown. To further characterize the genetic basis of MmD, we analyzed a series of 62 patients through a combined positional/candidate-gene approach. On the basis of clinical and morphological data, we suspected a relationship between classical MmD and the selenoprotein N gene (SEPN1), which is located on chromosome 1p36 (RSMD1 locus) and is responsible for the congenital muscular dystrophy with rigid spine syndrome (RSMD). A genomewide screening, followed by the analysis of 1p36 microsatellite markers in 27 informative families with MmD, demonstrated linkage to RSMD1 in eight families. All showed an axial myopathy with scoliosis and respiratory failure, consistent with the most severe end of the classical MmD spectrum; spinal rigidity was evident in some, but not all, patients. We excluded linkage to RSMD1 in 19 families with MmD, including 9 with classical MmD. Screening of SEPN1 in the 8 families that showed linkage and in 14 patients with classical sporadic disease disclosed 9 mutations affecting 17 patients (12 families); 6 were novel mutations, and 3 had been described in patients with RSMD. Analysis of three deltoid biopsy specimens from patients with typical RSMD revealed a wide myopathological variability, ranging from a dystrophic to a congenital myopathy pattern. A variable proportion of minicores was found in all the samples. The present study represents the first identification of a gene responsible for classical MmD, demonstrates its genetic heterogeneity, and reassesses the nosological boundaries between MmD and RSMD.
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PMID:Mutations of the selenoprotein N gene, which is implicated in rigid spine muscular dystrophy, cause the classical phenotype of multiminicore disease: reassessing the nosology of early-onset myopathies. 1219 40

Selenoprotein N-related myopathy (SEPN1-RM) is an early-onset muscle disorder that can manifest clinically as congenital muscular dystrophy with spinal rigidity and can result in specific pathological entities such as multiminicore disease, desmin-related myopathy with Mallory body-like inclusions, and congenital fiber-type disproportion. Here we describe the clinical, histopathological, muscle magnetic resonance imaging (MRI) and genetic findings of three Italian SEPN1-RM families. Proband 1 is a 31-year-old female who was floppy at birth and developed axial and mild lower limb-girdle weakness. The second proband is a 13-year-old boy with RSMD1. Probands 3 and 4 were brothers showing clinical phenotype of congenital myopathy. Muscle MRI demonstrated selective involvement of sartorius, gluteal muscles and distal gastrocnemius and sparing of rectus femoris and gracilis. Muscle histopathology showed in proband 1 myopathic changes with mild connective tissue increase and some fibres lacking the Z-line, while probands 2 and 3 had multiminicores. SEPN1 gene analysis revealed five mutations, three of which are novel. Proband 1 was a compound heterozygote for a 92-bp (exon 1) and a 1-bp deletion (exon 9); proband 2 had a 99-bp deletion and a 10-bp duplication in exon 1, and proband 3 presented a novel homozygous mutation in intron 10 acceptor splice site.
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PMID:New molecular findings in congenital myopathies due to selenoprotein N gene mutations. 2093 10