Association of plasminogen activator inhibitor-type 1 (PAI-1) -675 4G/5G polymorphism with unexplained female infertility

BACKGROUND: Infertility is a major issue of concern for couples at reproductive age.  The underlying causes of infertility remain unknown in 15-30 % of the cases. Plasminogen activator inhibitor type 1 (PAI-1), which is a major fibrinolytic factor, has been associated with increased infertility risk.  DNA variants at PAI-1, such as -675 4G/5G promoter polymorphism, have been implicated in infertility-related reproductive disorders, possibly due to a molecular mechanism involving implantation failure. This study aims to investigate the association of PAI-1 4G/5G polymorphism to otherwise unexplained female infertility in a sample of women of Greek ethnic origins. METHODS: We enrolled in this study 222 women from the population of Northern Greece; 115 women with unexplained infertility (group 1) and 107 normal fertile women (group 2). All participants were genotyped for PAI-1 -675 by real-time polymerase chain reaction. RESULTS: Our results indicate an association with the PAI-1 4G allele in our sample of women with unexplained infertility. The dominant genetic model supports the association, in contrast to the recessive genetic model. CONCLUSIONS: Our results indicate that PAI-1 4G/5G polymorphism is a promising screening factor which could potentially be a target for certain cases of unexplained female infertility. However, they should be interpreted with caution and should be validated in larger studies and diverse populations. In addition, other variants in genes involved in thrombophilia might need to be considered. HIPPOKRATIA 2017, 21(4): 180-185.