Clinical and Genetic Characteristics of Limb-Girdle Muscular Dystrophy in Iranian Patients

Background: Limb-girdle muscular dystrophy (LGMD) is a bothersome muscle disease associated with weakness of the shoulder and pelvic girdle. Objectives: The study aimed to determine the genetic diversity and relative frequency of various forms of LGMD in Iranian children. Methods: In this descriptive research, 60 children referred to the neurology or emergency department of the Pediatric Medical Center were studied from April 2019 to April 2020. Additional tests (muscle biopsy and genetic testing) were performed to confirm the diagnosis of LGMDs. Quantitative data such as disease level, motor, respiratory, and cardiac functions, and molecular data underwent statistical analysis. Results: A total of 41 patients with a mean age of 11.1 were studied. Twenty-two patients were diagnosed with genetic tests and 19 with muscle biopsies. Also, there were 26.8% cases of alpha sarcoglycanopathy, 24.4% beta sarcoglycanopathy, 17.1% gamma sarcoglycanopathy, 7.3% calpainopathy, 7.3% dysferlinopathy, 7.3% dystroglycanopathy, 7.3% titinopathy, and one case of laminopathy. Among genetically confirmed individuals, 27.3% had SGCB mutation, and 18.2% had SGCA mutation. A significant relationship was seen between the mutation type and creatine phosphokinase (CPK) levels (P < 0.05). Conclusions: The prevalence of alpha and beta sarcoglycanopathy phenotypes in the study population showed that the severity of clinical involvement may be predicted by SGCB gene mutation and sarcoglycan expression.