Exome sequencing reveals a homozygous frameshift variant in CAPN3 in a Tunisian patient with a neuromuscular disorder

Abstract

Muscular dystrophy (MD) is a heterogeneous group of diseases that cause progressive weakness and loss of muscle mass. Specific signs and symptoms begin at different ages and in different muscle groups, depending on the type of muscular dystrophy. We report here a case of a Tunisian patient suffering from a neuromuscular disorder, highly suspicious of a Limb-Girdle Muscular Dystrophy (LGMD). Exome Sequencing revealed a one-base deletion variant in exon 4 of the CAPN3 gene. CAPN3 is associated with a recessive form of LGMD, also known as Muscular Dystrophy, Limb-Girdle, Type 2a (LGMD2A). The variant was shown to segregate with the disease in the family. The identification of the molecular defect in this family provided a rapid genotyping for the sister and an accurate diagnosis for the patient, allowing appropriate clinical management at an early stage of the disease.