Phenotype and sarcoglycan expression in Tunisian LGMD 2C patients sharing the same del521-T mutation.

Abstract

Limb-girdle muscular dystrophy type 2C is an autosomal recessive muscular disorder caused by mutations in the gene encoding the gamma-sarcoglycan subunit. This gamma-sarcoglycanopathy is prevalent in Tunisia where only one homozygous mutation a 521-T deletion has been identified. The aim of this study was to carry out a comparative clinical and immunocytochemical analysis of Tunisian patients sharing the same gamma-sarcoglycan gene mutation. One hundred and thirty-two patients were classified as severe, moderate or mild according to a calculated severity score. Heterogeneous phenotypes between siblings were encountered in 75% of the families. The severity of the disease was not found to be related to the age of onset. Immunohistochemical studies of muscle biopsy showed a total absence of gamma-sarcoglycan, a normal or slightly reduced alpha and delta-sarcoglycans whereas the expression of beta-sarcoglycan was variable. The residual sarcoglycan expression was not related to the clinical phenotype. In conclusion, the phenotypic variability in sarcoglycanopathies in Tunisia seems to involve a modifying gene controlling the course of the disease.

• Authors: M Kefi, R Amouri, A Driss, C Ben Hamida, M Ben Hamida, L M Kunkel, F Hentati
• Journal: Neuromuscular disorders : NMD (Neuromuscul Disord) Vol. 13 Issue 10 Pg. 779-87 (Dec 2003) ISSN: 0960-8966 [Print] England
• PMID: 14678800 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Cytoskeletal Proteins
• DAG1 protein, human
• Membrane Glycoproteins
• Sarcoglycans
• Dystroglycans

Topics

• Adolescent
• Adult
• Age of Onset
• Child
• Child, Preschool
• Cytoskeletal Proteins (deficiency, genetics, metabolism)
• DNA Mutational Analysis
• Dystroglycans
• Environment
• Female
• Gene Expression Regulation (genetics)
• Genetic Testing
• Genetic Variation (genetics)
• Genotype
• Humans
• Immunohistochemistry
• Male
• Membrane Glycoproteins (deficiency, genetics, metabolism)
• Muscle, Skeletal (metabolism, pathology, physiopathology)
• Muscular Dystrophies (genetics, metabolism, pathology)
• Mutation (genetics)
• Phenotype
• Sarcoglycans
• Tunisia