Quantitative analysis of follistatin (FST) promoter methylation in peripheral blood of patients with polycystic ovary syndrome

Epigenetic mechanisms may contribute to polycystic ovary syndrome (PCOS). To date, however, no studies have associated CpG methylation levels of any candidate gene with PCOS susceptibility. Follistatin (FST), an activin-binding protein, is expressed in numerous tissues and is shown to have linkage with PCOS. However, results from case-control association analyses between this gene and PCOS are inconsistent. Thus, this study investigated possible association of methylation levels in the promoter and 5'-untranscribed region (UTR) of the FST gene with PCOS incidence in peripheral blood leukocytes and endometrial tissue. Using mass array quantitative methylation analysis, first the 5'-UTR methylation in FST was analysed in 130 PCOS patients and 120 controls. The methylation level of the FST gene was further studied in endometrium from 24 controls and 24 PCOS patients. This study demonstrates that methylation levels of CpG sites in the FST promoter and 5'-UTR are not associated with PCOS. Nonetheless, this was the first study to quantitatively evaluate the methylation levels of a candidate gene in association with PCOS. Further studies should be performed to examine methylation in other candidate genes. Understanding the epigenetic mechanisms involved in PCOS may yield new insights into the pathophysiology of the disorder. RBMOnline (C) 2012, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.