Differential Methylation of the Genes PAX8 and GATA4 Alters Their Expression in the Heart during Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common hereditary heart disease with a prevalence ranging from 1 : 500 to 1 : 200 individuals. The development and clinical presentation of HCM do not always conform to the traditional view of its monogenic inheritance pattern. One key to addressing this issue may lie in identifying epigenetic mechanisms regulating gene expression, particularly DNA methylation, involved in the pathogenesis of the disease and modifying its course. Using previously obtained whole-genome data, we identified four extended genomic regions with reduced methylation levels in the myocardium of patients with HCM. These include region chr2:113993204-113994075, located within the transcribed area of the PAX8 gene, as well as three other regions (chr6:31148369-31148577, chr8:11565217-11567212, and chr8:22132791-22133357), which are associated with promoters of genes PSORS1C3, GATA4, and PIWIL2, respectively. We demonstrated altered expression of PAX8 and GATA4 genes containing one each of these four mentioned regions. Our findings will expand the currently very limited understanding of the unique features of epigenetic regulation in this condition.