Abstract: 【Abstract】The androgen receptor gene locates on chromosome Xq11-12; its first exome exists in CAG repeat sequence; while (CAG)n repeat sequence is polymorphism in different race and region. The repeat number or length of androgen receptor gene (CAG)n shows a negative correlation with androgen receptor (AR) activation of Polycystic ovarian syndrome (PCOS); whereas androgen levels are positively correlated; and (CAG)n polymorphism affects the related features of PCOS, such as insulin resistance, formation of acne and hairy. Short or fewer repeat number of (CAG)n may increase susceptibility to PCOS patients. Whereas the inactivation of X chromosome can adjust the AR effect; supposing inactivation of X chromosome does have effect on AR, and longer or higher repeat number of (CAG)n can increase the risk of PCOS. This article reviews the influence of androgen receptor gene (CAG)n polymorphism on the formation of PCOS.

Key words: 【Key Words】 Polycystic ovarian syndrome, Androgen receptor gene, (CAG)n polymorphism