A family is described in which 5 of 9 living children were found to have restrictive cardiomyopathy associated with skeletal muscle and orthopedic abnormalities. In the absence of another identifiable etiology, a genetic cause for restrictive cardiomyopathy in this family is probable. Consistent with the poor prognosis encountered for children with restrictive cardiomyopathy, 2 children in this family died, whereas a third was symptomatic by age 3 years. [Copyright &y& Elsevier]