Vascular endothelial growth factor (VEGF) polymorphisms in HELLP syndrome patients determined by quantitative...

The vascular endothelial growth factor (VEGF) has a critical role in vasculogenesis and vascular permeability in several diseases including preeclampsia. There are at least 30 single nucleotide polymorphic (SNP) places on this gene. VEGF G+405C, C-2578A and C-460T SNPs are known to be related to VEGF production. VEGF polymorphisms were studied in preeclampsia, but not in HELLP syndrome. Therefore, we decided to determine the allele and genotype frequencies of VEGF G+405C, C-460T and C-2578A SNPs in healthy pregnant women and HELLP syndrome patients.

The authors introduced a quantitative real-time PCR method for the determination of the three VEGF SNPs. Blood samples were collected from 71 HELLP syndrome patients and 93 healthy controls. DNA was isolated by using silica adsorption method. The SNPs were determined by quantitative real-time PCR and melting curve analysis using LightCycler.

There were significant differences in the allele and genotype frequencies of VEGF C-460T SNP between the two study groups. The T allele was present in 71.1% in the HELLP group, while in 53.8% in the controls (p=0.0014). The TT genotype occurred significantly more frequently in the HELLP group than in the control group (45.1% vs. 21.5%; p (for genotype frequencies)=0.0011). The TT genotype carriers had an increased risk of HELLP syndrome, which was independent of maternal age and primiparity (adjusted odds ratio (OR)=3.03, 95% confidence interval (CI)=1.51-6.08; p=0.002). Although the VEGF G+405C allele and genotype distributions did not differ significantly between the two groups, the CC genotype carriers were also found to have an increased risk for HELLP syndrome after adjustment for maternal age and primiparity (adjusted OR=3.67, 95% CI=1.05-12.75; p=0.041). The VEGF C-2578A SNP was not associated with HELLP syndrome.

The quantitative real-time PCR combined with melting curve analyses is a fast and reliable method for the determination of VEGF SNPs. We found that the VEGF -460TT and +405CC genotype carriers have an increased risk of HELLP syndrome. As these two SNPs were previously observed to be related to production of the VEGF protein, we suppose that these VEGF polymorphisms -- interacting with other genetic and environmental factors - could play a role in the development of HELLP syndrome.