Internet Databases Offer Easy Access to Relevant Genetic Information
Kathleen Jaques Bennett, BSc, BSc, MSc
Familial hypertrophic cardiomyopathy (FHCM) is an inherited disorder that results in the thickening and stiffening of the myocardium, primarily in the left ventricle.1 This disorder runs in families and may appear late in life. FHCM is produced by mutations in at least eight autosomal genes that are responsible for the synthesis of the sarcomeric filament proteins. These genes vary in terms of where the mutations are located.2 FHCM is present in less than 0.5% of the population and has been associated with sudden death.3 The disorder varies both in its severity and in its clinical features, with more variants still being identified. There is some phenotypic heterogeneity with FHCM but the disorder is highly correlated in its physical expression to the mutation and its location, especially within families. Internet-based databases now exist to describe the characteristics of FHCM, specific mutations and loci, the epidemiology and the type of hypertrophy and the prognosis.4 FHCM has been a disorder associated with young people but was recently identified as having a late-onset variant that develops after age 50. This late-onset FHCM results from mutations in the gene for cardiac myosin-binding protein C (MBP-C) and cardiac troponin T (TNN-T).