In this work, to identify aberrantly methylated DNA molecules that appear in the blood during the development of prostate cancer, the methylation status of individual cytosines in the CpG dinucleotides of the promoter regions of the GSTP1, RNF219, and KIAA1539 genes was analyzed using locus-specific NGS sequencing. The gene discussed is ATOSB; the disease is prostate carcinoma.