Decreased expression of dysferlin supports the diagnosis of dysferlinopathy, but it should be noticed that the expression of dysferlin may also decrease secondary to deficiency of other related genes, such as CAPN3 (causative gene for LGMD R1), so genetic analysis remains the definitive diagnostic criterion for dysferlinopathy. This evidence concerns the gene CAPN3 and neuromuscular disease caused by qualitative or quantitative defects of dysferlin.