The vascular endothelial growth factor +405G>C polymorphism in endometriosis

BACKGROUND: Vascular endothelial growth factor (VEGF) is a potent stimulus of angiogenesis potentially contributing to the pathogenesis of endometriosis. The aim of this study was to investigate the potential association between the single nucleotide polymorphism +405G>C of the VEGF gene with the risk of endometriosis, for the first time in the Caucasian population. METHODS: The polymorphism +405G>C of the VEGF gene was examined in n = 203 Italian women affected by endometriosis and in n = 140 women without laparoscopic evidence of the disease. All the women were genotyped by PCR-restriction fragment length polymorphism from venous blood samples. We then performed a meta-analysis including results from the present study and from the two previously published studies on this topic. RESULTS: The distribution of the three different genotypes significantly differed between women with and without the disease (P = 0.03). The odds ratio (95% confidence interval) for endometriosis in women carrying the C allele was 1.8 (1.2-2.8). The Breslow-Day test revealed statistically significant heterogeneity among the studies performed so far thus indicating inconsistency among studies and excluding the possibility of obtaining a common estimation of the effect. CONCLUSIONS: Results obtained herein are in keeping with those obtained previously and support a role for the +405G>C VEGF polymorphism in endometriosis development, although a further, larger study is required to confirm our findings. However, this effect may depend on the population studied. Ethnicity and the characteristics of endometriosis are likely to influence this association.