DNA methylation associated with polycystic ovary syndrome: a systematic review

Purpose Polycystic ovary syndrome (PCOS) is an endocrine metabolic disease that affects women of reproductive age and is one of the main causes of anovulatory infertility. However, the cause of PCOS is yet fully understood, and genetic factors play an important role in its etiology. In this study, we reviewed the main genes involved in the etiology of PCOS and the influence of DNA methylation, aiming to answer the studys guiding question: 'What is the influence of DNA methylation on the main genes involved in PCOS?'. Methods We used the MEDLINE database, and inclusion criteria (primary and original articles, written in English, found through our entry terms) and exclusion criteria (literature reviews and articles that used animals to perform the experiments and that focused in other epigenetics mechanism without being DNA methylation) were applied. Results Twenty-three scientific articles, from a total of 43 articles read in full, were chosen for this study. Eighteen studies confirmed DNA methylation associated with PCOS. Conclusion The most relevant genes related to PCOS were INSR, LHCGR, and RAB5B, which may be epigenetically altered in DNA, with the first two genes hypomethylated and the last hypermethylated. The epigenetic changes presented in the genes related to PCOS or their promoters were only at the CpG sites.