Sex-Specific Age-Related Changes in Methylation of Certain Genes.

The aim of the study was to conduct a functional analysis of sex-specific age-related changes in DNA methylation.

Materials and methods: The study used a GSE87571 methylation dataset obtained from the blood DNA of 729 individuals aged 14 to 94 using the Illumina Infinium HumanMethylation450K BeadChip (USA). Gene ontology analysis was performed for 3 groups of genes (females, males, and duplicates) using the PANTHER database. The DAVID platform was used to perform KEGG metabolic pathway analysis.

Results: The studies revealed unique for males and females changes in methylation of CpG sites, associated with certain metabolic processes. It was demonstrated that most of the CpG sites, for which methylation changes with age were revealed in both sexes, are associated with the genes responsible for the development and functioning of the nervous system. In males, unique age-related methylation changes affect CpG sites associated with changes in the immune system and lipid metabolism. In females, most CpGs are associated with changes involved in transcription and translation processes. Analysis of biological functions by KEGG revealed that a unique process associated with age-related changes in methylation of the glutamatergic system is typical for males. In females, unique biological processes with age-related changes include genes responsible for the development of diabetes and genes associated with cAMP signaling cascades (KEGG:04024).

Conclusion: Our studies reveal fundamental features of sex-dependent changes in methylation of CpG sites with variance increasing, which may indicate differences in age-related changes.