expression in PCOS patients is not significant. (p = 0.076). A significant negative association has been seen between the mRNA. There is a significant negative correlation between the mRNA expression of the HSD17B1 gene and serum E2 levels. (p = 0.020). "The more down-regulated mRNA expression of the HSD17B1 gene, the lower serum E2 levels." The integrated analysis in this study was hypomethylated DNA and down-regulated mRNA expression of HSD17B1 genes. The hypomethylated DNA was not involved in down-regulating mRNA expression. Therefore, down-regulated mRNA expression of the HSD17B1 gene in PCOS patients can cause lower E2 levels in PCOS, preventing cell growth and potentially contributing to the cause of PCOS pathogenesis.