Variable cardiac involvement in Tunisian siblings harboring FKRP gene mutations

Mutations in the gene encoding fukutin-related protein (FKRP) cause limb-girdle muscular dystrophy 2I (LGMD2I) and congenital muscular dystrophy (MDC1C). Cardiac involvement was frequently reported with numerous mutations including C826A and 1364C > A mutations. The original Tunisian family with LGMD2I included 12 patients sharing the LGMD phenotype and homozygous to the 1486T > A mutation but who did not display any cardiac involvement. In this study, we report the clinical data, cardiac assessment and mutation analysis in four sibs belonging to a second Tunisian LGMD2I family. All patients showed the LGMD phenotype, the oldest brother and sister had mild cardiac involvement, whereas two twin sisters displayed severe cardiomyopathy leading to death. The patients shared the compound heterozygous 1486T > A, 1364C > A mutation in the FKRP gene suggesting that the association of a compound heterozygous state of mutation responsible for LGMD2I and the MDC1C phenotype could lead to cardiac involvement.