Factors underlying PCOS can downregulate Dnmt1 expression, which may lead to abnormal methylation of the MAPK pathway-related gene Map3k1 and the autophagy-related gene Map1lc3a. We observed that in the PNA mice’s ovaries, autophagy was significantly increased, especially in granulosa cells. The gene discussed is DNMT1; the disease is polycystic ovary syndrome.