In women with PCOS, high concentrations of leptin have been reported to inhibit the expression of aromatase mRNA in granulosa cells, while the hyperandrogenic follicular environment in GCs was found to significantly reduce the expression of P450arom, which can convert androgens into estrogen, further increasing the levels of androgens and ultimately promoting follicular atresia (148–150). The gene discussed is CYP19A1; the disease is polycystic ovary syndrome.