BRD2 and polycystic ovary syndrome: According to previous reports, the diversity of gut microbiota is reduced in patients with PCOS; Several specific bacterial species including Bacteroidetes and Firmicutes are found to have an abnormal abundance in PCOS, and these changes in gut microbiota reveal strong correlations with PCOS manifestations encompassing estradiol (E2), testosterone (T), luteinizing hormone (LH), and follicle-stimulating hormone (FSH; Torres et al., 2018; Zhou et al., 2020a; Dong et al., 2021).