Polymorphism of CAG Repeat in Androgen Receptor Gene in Egyptian Women with Polycystic Ovary Syndrome

Background: Trinucleotide repeats CAG (n) in androgen receptor gene is thought to be central to PCOS genetic susceptibility. However, previous studies of PCOS have shown variable association of CAG (n) polymorphism with PCOS. Objective: To assess the association of the AR gene CAG repeat length polymorphism with PCOS among Egyption patients, and its influence on clinical and biochemical androgen traits. Patients and Method: A cohort of 80 women with oligoanovulatory cycles and ultrasound features of PCOS and 67 healthy women of reproductive age were investigated for CAG repeat lengths using genescan. Assay of serum total testosterone, free testosterone and DHEAS were carried out. These parameters were correlated with the CAG repeat. Results: AR (CAG) n range were 8-25 with a median of 19 in PCOS patients and 10-29 with a median of 22 in control group. The difference in median repeat number was significant comparing PCOS with control ( p<0.001). A higher frequency of short AR (CAG) n alleles ( 9 15) tended to be more frequent in PCOS women than controls (p=0.005). We found significant difference between the both groups as regard BMI, Hirsutism, Total testosterone, Free testosterone and DHEAS. Conclusion: Our findings support the hypothesis that there is association of shorter CAG repeats with Egyption PCOS patients suggesting inherited alteration in androgen sensitivity may contribute to PCOS.