A major cause of heart disease in all age groups.
Onset often in adolescence or early adult life.
Classified as hypertrophic, dilated, restrictive, arrhytmogenic right ventricular, and other types.
Different mutations in the same gene can underlie different disorders, so that mutations that affect adjacent amino acids in the beta-myosin heavy chain can cause either hypertrophic cardiomyopathy were dilated cardiomyopathy (Kamisago M et al).
Genetically heterogeneous, with multiple genetic abnormalities, and many different mutations.