A Child cohort study from South Italy enlarges the genetic spectrum of Hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is the most frequent common genetic cardiovascular disorder worldwide. It is the leading most frequent cause of sudden cardiac-related death in young people and a major cause of cardiac failure and death in the elderly. However, HCM frequently goes undiagnosed until the appearance of overt signs and symptoms, thereby delaying prophylactic and therapeutic measures. We screened patients for sarcomeric genes associated with HCM to obtain information that could be useful for an early diagnosis and so limit the severe consequences of silent HCM. We recruited 39 HCM families from Southern Italy and found mutations in 41% of families (12 with familial HCM and 4 with sporadic HCM). The remaining 23 families (59%) were negative for myofilament gene mutations. Of the 12 mutations identified, 8 were novel. Screening of the other family members available revealed that 27 had mutations; 11 of these subjects had no signs or symptoms suggestive of HCM. This study, besides characterizing the spectrum of mutations in another childhood population, and revealing an even greater genetic heterogeneity than formerly recognized, may increase genotype-phenotype correlations, and thus may help to identify asymptomatic candidates for early preventive or therapeutic measures.