In addition to the conflicting data on the association between genetically encoded CAG repeats and PCOS, we should consider the X chromosome inactivation (XCI) as a significant phenomenon present in females because the AR gene is located on the X chromosome; therefore, the AR activity is determined not only by the AR genotype but also by the epigenetic effect of XCI [69]. The gene discussed is AR; the disease is polycystic ovary syndrome.