Cardiomyopathy, Familial Hypertrophic, 14
A number sign (#) is used with this entry because familial hypertrophic cardiomyopathy-14 is caused by mutation in the MYH6 gene (160710).
For a phenotypic description and a discussion of genetic heterogeneity of familial hypertrophic cardiomyopathy, see CMH1 (192600).Molecular Genetics
In a study of late-onset hypertrophic cardiomyopathy (CMH), Niimura et al. (2002) reported a 75-year-old woman in whom they identified a heterozygous mutation in the MYH6 gene (R795Q; 160710.0002). The patient, who became symptomatic at age 74 years, had a maximum left ventricular wall thickness of 19 mm.
Carniel et al. (2005) analyzed the MYH6 gene in 21 CMH families, including 29 affected and 30 unaffected individuals, and identified a heterozygous mutation (Q1065H; 160710.0004) in 1 Caucasian proband that was not found in 150 ethnically similar controls. The patient was diagnosed with CMH at 27 years of age, at which time the maximal wall thickness was 23 mm, and died of refractory congestive heart failure while awaiting heart transplantation at age 45 years. Family history was significant for sudden death of the proband's mother at age 47 years; the proband's 2 offspring were clinically unaffected and did not carry the mutation. Mutations in 3 known CMH-causing genes (MYH7, 160760; TNNT2, 191045; and MYBPC3, 600958) were excluded in the patient.