The prevalence of 4G5G polymorphism of plasminogen activator inhibitor-1 (PAI-1) gene in polycystic ovarian syndrome and its association with plasma PAI-1 levels.

OBJECTIVE

To investigate the prevalence of 4G5G polymorphism of plasminogen activator inhibitor-1 (PAI-1) gene in polycystic ovary syndrome (PCOS) and its functional significance.

DESIGN

Case-control study.

METHODS

We studied 98 patients and 64 controls. Body mass index (BMI) and waist-to-hip (WHR) ratio were determined. Blood samples were obtained for DNA analysis. PAI-1 plasma levels, serum total testosterone, fasting insulin and fasting glucose were measured and the glucose-to-insulin ratio was estimated in all subjects.

RESULTS

There was a statistically significant difference in the distribution of PAI-1 gene variations among the groups. The PCOS group had significantly higher 4G/4G and 4G/5G combinations than the control group, whereas there were significantly less 5G/5G. Among the PCOS women, 39.8% had the genotype 4G/4G, 39.8% 4G/5G and 20.4% 5G/5G. From the control group, 20.3% had genotype 4G/4G, 28.1% 4G/5G and 51.6% 5G/5G. In the 4G/4G genotype subgroup 75% were PCOS and 25% were controls, in the 4G/5G were 68.42% and 31.58% and in the 5G/5G were 31.58% and 62.26% respectively. The population of PCOS women had significantly higher PAI-1 levels, WHR, total testosterone, and fasting glucose than the population of controls.

CONCLUSIONS

1) The genotypic subtypes 4G/4G and 4G/5G, in PCOS, were present with a statistically higher frequency compared with controls. 2) PCOS women have higher levels of PAI-1 compared with the control group. 3) The presence of the 4G allele in PAI-1 promoter region of the gene further increases the PAI-1 levels.