CYP11A1 microsatellite (tttta)n polymorphism in PCOS women from South India

Polycystic ovary syndrome (PCOS) is a condition with central feature of hyperandrogensism that affects 5-12 % of women worldwide. P450sec the cholesterol side chain cleavage enzyme encoded by CYP11A1 gene is instrumental in the synthesis of sex hormones. A promoter pentanucleotide repeat (tttta)(n) polymorphism of this gene is reported to be associated with several hormone related diseases including PCOS. Here we aimed to examine the involvement of CYP11A1 polymorphism with PCOS susceptibility in a case-control study conducted among South Indian women. A total of 542 subjects comprised of 267 PCOS patients and 275 controls were recruited. DNA was extracted from blood and CYP11A1 (tttta)(n) polymorphism was genotyped by PCR-PAGE. Fifteen different alleles ranging between 2-16 repeats were identified in the studied group and the most frequent allele observed in controls was of 8 repeats. The presence of > 8 repeat allele was common in patients (64 % vs. 38 %) and showed a three-fold risk for PCOS susceptibility than controls (OR = 2.93; p < 0.05). PCOS women with higher BMI were markedly elevated in early quartile (p < 0.05). CYP11A1 (tttta)(n) repeat polymorphism appeared to be a potential molecular marker for PCOS risk in our population. Gene-gene and gene-environmental interactions with respect to obesity may play a role in the early onset of this multifactorial condition. This is the first report from South India; however, replicative studies considering other probable causative factors for PCOS risk are warranted.