Family-based analysis of -675 4G/5G polymorphism in the PAI-1 gene of polycystic ovary syndrome in Chinese population.

Previous studies have shown that 4G/5G polymorphism in promoter region of plasminogen activator inhibitor-1 (PAI-1) gene can affect insulin sensitivity by elevating the level and activity of plasma PAI-1. In order to elucidate the relationship between the polymorphism of PAI-1 gene and polycystic ovary syndrome (PCOS), we used transmission disequilibrium test (TDT) to study the family of PCOS. Eight hundred and fifty-five participants consisting of 285 trios (mother, father and offspring with PCOS) were recruited at the Center of Reproductive Medicine, Shandong University from July 2007 to August 2014. 4G/5G polymorphism of PAI-1 gene was genotyped using direct sequencing protocol and TDT was used to analyse the association between PAI-1 gene and PCOS. Though the 5G allele in PAI-1 gene was overtransmitted in families, no statistical significance existed and there was no association between PAI-1 gene and PCOS, indicating that PAI-1 gene was unlikely to play a major role in the aetiology of PCOS in Chinese population.Impact Statement What is already known on this subject? Some studies have shown that 4G/5G polymorphism in promoter region of plasminogen activator inhibitor-1 (PAI-1) gene can affect insulin sensitivity by elevating the level and activity of plasma PAI-1, participating in the formation of insulin resistance (IR). What do the results of this study add? Though the 5G allele in PAI-1 gene was overtransmitted in families, no statistical significance existed and there was no association between PAI-1 gene and polycystic ovary syndrome (PCOS). What are the implications of these findings for clinical practice and/or further research? PAI-1 gene was unlikely to play a major role in the aetiology of PCOS.