Androgen receptor gene CAG repeat polymorphism in women with polycystic ovary syndrome

ObjectiveTo evaluate the role of the androgen receptor (AR) gene CAG repeat in women with polycystic ovary syndrome (PCOS).DesignCase control study.SettingUniversity department of obstetrics and gynecology.Patient(s)Women with (n = 114) or without (n = 205) PCOS.Intervention(s)Peripheral blood sampling was done for DNA analysis and serum hormone measurements.Main Outcome Measure(s)CAG repeat length and serum androgen levels.Result(s)No statistically significant CAG repeat length differences were found between patients and controls. We conducted a detailed analysis after dividing PCOS patients according to their free testosterone levels. The high free testosterone group had a statistically significantly longer mean biallelic average (24.0 ± 2.0 vs. 23.0 ± 1.5), short (22.5 ± 1.8 vs. 21.7 ± 1.9), and long (25.5 ± 2.9 vs. 24.4 ± 1.9) allelic lengths than the normal free testosterone group. In PCOS patients, a statistically significant correlation was found between biallelic average length and free testosterone concentration, either unadjusted or after adjustment.Conclusion(s)The AR gene CAG repeat polymorphism may contribute to the serum concentration of free testosterone in PCOS patients. A subset of PCOS patients with relatively longer CAG repeats (less AR activity) tended to show a higher serum androgen concentration.