Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD) and merosin-deficient congenital muscular dystrophy type 1 (MDC1A) are frequent forms caused by DMD (NM_004006.3) and LAMA2 (NM_000426.4) mutations, respectively. The gene discussed is LAMA2; the disease is Duchenne muscular dystrophy.