Although the frame rule (and its exceptions) explains the genotype-phenotype relationship in the majority of DMD gene pathogenic variations (mutations) causing Duchenne and Becker muscular dystrophies, intermediate phenotypes, and isolated cardiomyopathy (XLDC), the etiopathogenesis of sparse and rare asymptomatic or non-classic dystrophic cases remains largely unexplained. Here, DMD is linked to Becker muscular dystrophy.