Does follistatin gene have any direct role in the manifestation of polycystic ovary syndrome in Indian women?

Out of a panel of 37 candidate genes tested for linkage with polycystic ovary syndrome (PCOS), the strongest evidence of linkage was reported in the follistatin (FST) gene region. Subsequently, a couple of studies outside India investigated the FST gene for the presence of any mutations and its association with PCOS and the results were found to be largely inconsistent probably due to differences in the ethnic backgrounds and small sample sizes. To screen the FST gene for mutations and to establish their association pattern with PCOS among a large cohort of South Indian women. Case-control study. PCOS cases were recruited according to the 2003 Rotterdam diagnostic criteria. All the exons of the FST gene were amplified and analyzed in all the cases and controls for the presence of mutations using polymerase chain reaction (PCR) and direct DNA sequencing. A total of 549 women consisting of 250 PCOS cases and 299 controls were recruited for the study. No mutations were found in any of the exons of the FST gene in our Indian sample which is consistent with an earlier finding among the Asian women from Singapore. Although three of the four cohorts of Caucasian background studied earlier reported variants, none of them could establish a strong association with PCOS. The occurrence of the exonic variants of FST gene seems to be dependent on the ethnic background of the subjects under study and its role in the PCOS pathophysiology cannot be established with hitherto available evidence.