Genetics of hypertrophic cardiomyopathy in Norway

Genetic testing for hypertrophic cardiomyopathy ( HCM ) became available in Norway in 2003. Here, we describe the results of this testing in probands with HCM referred until the end of 2012. The translated exons of MYBPC3 , MYH7 , TNNI3 , TNNT2 , MYL2 and MYL3 were analyzed in two groups of probands. In Group 1, comprising 696 probands above 1 year of age, a mutation was found in 203 patients (29.2%). Of those, 5.9% were carriers of two mutations. Mean age in double mutation carriers, single mutation carriers and mutation negative probands was 44 years (±19 years), 50 years (±15 years) and 55 years (±16 years), respectively. In Group 2, comprising 26 infants below the age of 1, a mutation was found in 15.4%. A total of 120 different mutations were found of which 51 (42.5%) were novel.