Preeclampsia is a severe complication of pregnancy characterized by an excessive maternal systemic inflammatory response with activation of both the innate and adaptive immune system. Interleukin-10 affects maternal intravascular inflammation, as well as endothelial dysfunction. The aim of the study was to investigate the association between IL-10 T-819 C polymorphism and preeclampsia. A total of 120 pregnant women with preeclampsia and 120 women with normal pregnancy attending the Gynecological Unit of Government Maternity Hospital, Petlaburz, Hyderabad, India, were considered for the present study. A standard amplification refractory mutation system (ARMS) PCR was carried out for genotyping of IL-10 T-819 C promoter polymorphism in all the participants. Genotypic distribution of the control and patient groups was compared with values predicted by the Hardy-Weinberg equilibrium using χ2 test. Odds ratios (OR) and their respective 95 % confidence intervals were used to measure the strength of association between IL-10 gene polymorphism and preeclampsia. The frequencies of IL-10 T-819 C genotypes, CC, CT, and TT, were 47.5, 28.3, and 24.2 % in women with preeclampsia and 20.8, 48.3, and 30.8 % in the controls, respectively. There is a significant difference in the distribution of genotypes and alleles of IL-10 T-819 C between the two groups (test power = 0.66). The present study suggests that the IL-10 T-819 C gene promoter polymorphism can be a major genetic regulator in the etiology of preeclampsia.

SummaryPre-eclampsia is one of the most serious disorders of human pregnancy and T helper type 1 (Th1)/Th2 imbalance plays a major role in its aetiology. The Th2 cytokine, interleukin (IL)-10, plays a significant role in the maintenance of pregnancy. The present study is aimed at understanding the role of IL-10 promoter polymorphisms (−1082 G/A; −592 A/C and −819 C/T) and their haplotypes in early-onset pre-eclampsia. A total of 120 patients and an equal number of women with normal pregnancy, from Government Maternity Hospital, Petlaburz, Hyderabad, India, were considered for the present study. A standard amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) was carried out for genotyping followed by agarose gel electrophoresis. Appropriate statistical methods were applied to test for the significance of the results. It was found that the IL-10 −819 C allele (P = 0·003) and −592 A (P = 0·005) allele frequencies increased significantly in patients compared to controls. No significant difference was found with regard to −1082 promoter polymorphism. Haplotype analysis of the IL-10 single nucleotide polymorphisms (SNPs) revealed a significant association with ACC haplotype with a twofold increased risk in patients compared to controls. The frequencies of two common IL-10 haplotypes (GCC and ATA) did not show any significant difference. Further, the diplotype analysis revealed five genotypes: −1082A with −819C (P = 0·0016); −1082G with −819C (P = 0·0018); −819C with −592C (P = 0·001); −1082A with −592C (P = 0·032); and −1082G with −592C (P = 0·005) associated with the disease. These findings support the concept of contribution of IL-10 gene polymorphisms in the pathogenesis of early-onset pre-eclampsia.

The present study suggests that the IL-6 -174 promoter polymorphism is a major genetic regulator in the etiology of early-onset preeclampsia.