A Novel Founder Mutation in the SGCB Gene Causes Severe Form of Limb Girdle Muscular Dystrophy (LGMD) 2E in Sathwara Community

Autosomal recessive limb girdle muscular dystrophy (LGMD2) is characterized by progressive skeletal muscle weakness. Its onset, advancement and severity of the weakness may vary depending on the genetic subtypes like LGMD2C, LGMD2D, LGMD2E, LGMD2F. Among these the most common subtype in Indian population is LGMD2C. Although, LGMD2E is relatively rare subtype, in present study we report clinical and genetic data of 6 children diagnosed as LGMD2E with same novel mutation (Chr 4:52894204C>T; c.683G>A; p.Gly228Glu) in SGCB gene from three distinct families of Sathwara community of Gujarat, India. The identified novel missense mutation present on extracellular domain of SGCB protein resulting in its conformational change may leads to modification of sarcoglycan complex assembly results in sarcoglycanopathy. This novel mutation was found in three unrelated families of Sathwara community suggesting its high prevalence with founder effect.

What this paper adds:  Multiple families with LGMD2E, uncommon type of sarcoglucanopathy  Paper reports a Novel Mutation in SGCB gene  This mutation has a founder effect in Sathwara Community  Identified variant can be used as diagnostic marker for LGMD2E
Keywords: LGMD, Founder effect, India