Familial lethal cardiomyopathy with mental retardation and scapuloperoneal muscular dystrophy.

A family is described with a neuromuscular disorder characterised by possible X-linked recessive inheritance, a benign, slowly progressive muscular dystrophy with predominant humeroperoneal distribution and lack of contractures or pseudohypertrophy, central nervous system involvement, myopia and lethal cardiomyopathy. The possibility of cardiac transplant as life-saving therapy is suggested.