Objective: To assess the association of IFNG gene polymorphisms with preeclampsia among pregnant woman from Shaanxi Province.
Methods: Genomic DNA was extracted from peripheral blood samples collected from 280 patients with preeclampsia and 344 healthy pregnant women. Five tag single nucleotide polymorphisms (SNPs) of the IFNG gene (rs2069705, rs2430561, rs1861493, rs2069718, and rs2193050) were genotyped with a SNaPshot method. Genotypic and allelic frequencies were evaluated with a Chi square test. Genotype data was corrected by Logistic regression for body mass index and age. The level of IFN-gamma was determined with an ELISA assay.
Results: The distribution of five tag SNPs all conformed to Hardy-Weinberg equilibrium (P> 0.05). Significant association with preeclampsia was found with the T allele of rs2430561 (OR=1.54, 95% CI:1.15-2.09, P=6.99× 10-3), under a dominant model (OR=3.77, 95% CI: 1.09-13.29, P=0.029) and a recessive model (OR=1.53, 95% CI:1.09-2.15, P=0.018). For the patient group, the IFN-gamma level of those with a TT genotype for rs2430561 was significantly higher than those with an AA or AT genotype [(13.69± 0.79) pg/mL vs. (13.11± 1.56) pg/mL, P< 0.05].
Conclusion: Polymorphism of the rs2430561 locus of the IFNG gene is associated with increased risk for preeclampsia as well as serum level of IFN-gamma among pregnant woman from Shaanxi. The role of the IFNG gene in the regulation of preeclampsia requires further investigation.