Familial hypertrophic cardiomyopathy.Insertion-deletion polymorphism of angiotensin-converting enzyme and angiotensin II receptor

Background: Hypertrophic cardiomyopathy (HCM) is a genetic-based disease. Several gene mutations leading to HCM development have been described. Aim: Detailed examination of phenotype and genotype of a family with HCM. Methods: Clinical and genetic examinations were performed in a family with HCM, in which 3 sick persons with different disease phenotype were found. Results: In all sick persons the same molecular substitution G->A (AGG->AAG) was noticed. It led to substitution Arg780-Lys in exon 21 β-myosin heavy chain gene, which was responsible for the development of the disease. Insertion- deletion polymorphism analysis in ACE gene revealed D/D (deletion/deletion) genotype in proband and D/I (deletion/ insertion) phenotype in his mother and sister, who were heterozygous. Polymorphism A1166C analysis in AT1 gene revealed the presence of genotype A/A in proband and A/C in his mother and sister. In proband and his sister a very similar phenotype was observed, whereas they had different polymorphism for ACE gene and angiotensin 1 receptor gene. In sick proband's mother, who had phenotype different to her children, the same polymorphism as in his daughter was noticed. Conclusions: In the described family with HCM, different phenotype and polymorphism of ACE and AT1 genes were found.