THE MYH7, MYBPC3 GENE MUTATIONS IN HYPERTROPHIC CARDIOMYOPATHY PATIENTS RESIDING IN THE REPUBLIC OF BELARUS
Introduction. Hypertrophic cardiomyopathy (HCM) is a common genetically heterogeneous disease caused by mutations in genes
encoding proteins of the cardiac sarcomere. Mutations in the genes encoding β-myosin heavy chain (MYH7) and myosin binding protein C
(MYBPC3) are found most frequently in HCM patients and these genetic defects are specific for different populations.
The aim of the study was to identify the spectrum of mutations in MYBPC3 and MYH7 genes in HCM patients residing in the republic
ofBelarus and to estimate phenotypic manifestations of these mutations.
Methods. We searched for mutations in exons 19, 20, 23 of the MYH7 gene and in exon 17of theMYBPC3 gene in 116 HCM patients with the
use of the automatic DNA sequencing; and 75 patients from the analyzed cohort were screened for mutations in exon 24 of the MYBPC3 gene.
Results and conclusion. The following mutations in the MYH7 gene were identified: Ala729Pro mutation in exon 20was found in three
unrelated patients with HCM, Glu924Lys mutation in exon 23 – in two unrelated patients and deletion Glu930del was found in one family.
Also Arg502Gln and Asn515del mutations were identified in exon 17of the MYBPC3 gene. Mutations in exon 19 of the gene MYH7 and in
exon 24of the MYBPC3 gene were not found. The genetic and clinical test results of immediate family members of patients were presented
and their genealogic trees were constructed.
All of identified mutations were previously described in patients with HCM in other populations. Some of the identified mutations were
unfavourable for HCM, others were associated with a better prognosis, but often the clinical features of the disease were heterogeneous, even
in patients with the same genetic defect.
Keywords:
hypertrophic cardiomyopathy, mutations in the MYH7, MYBPC3 genes