Association Between Interleukin-10 Gene Polymorphisms And Risk Of Early-onset And Late-onset Preeclampsia

Objective:we conducted a case-control study to investigate the role of IL-10-1082A/G(rs1800896),-819T/C(rs1800871),and-592A/C(rs1800872)polymorphisms in the development of early-onset preeclampsia and late-onset preeclampsia.Methods:1.Patients and groupingA case-control study was taken in our study.Cases can be divided into four groups,early onset preeclampsia group(155),early-onset preeclampsia control group(201),late-onset preeclampsia group(158)and the late-onset preeclampsia control group(200).The criteria of early-onset preeclampsia were presence of blood pressure values>140/90 mmHg,and proteinuria(24-hour urinary protein>300 mg or urine dipstick protein ? +)after 20 weeks of gestation.Patients who had a previous history of intrauterine fetal deaths were excluded from our study.controls with more than 20 weeks of gestation were randomly collected from the individuals who went to accept prenatal in our hospital during the same period.Controls that had chronic hypertension,a history of renal,autoimmune,metabolic or cardiovascular disease were excluded from our study.The demographic and clinical data of patients with early-onset preeclampsia and controls were collected from a self-designed questionnaire.2.experimental methodBefore the patients began their treatment,2 ml peripheral blood was collected with EDTAanticoagulant tubes.Genomic DNA was extracted from the blood,using the QIAamp DNA MAX Kit(Qiagen,Hilden,Germany).Polymerase chain reaction restriction fragment length polymorphism(PCR-RFLP)assay was applied to assess the polymorphisms of IL-10-1082A/G(rs1800896),-819T/C(rs1800871),and-592A/C(rs1800872)..PCR reactions were carried out with an initial denaturation step of 8 minutes at 94?,followed by 30 cycles at 94? for 30 seconds,annealing at 60? for 30 seconds,and extension at 72? for 1 minute.The DNA fragments were confimed through electrophoresing on 3.5%agarose gel and visualizing under UV light after ethidum staining.3.Statistical analysisContinuous variables were expressed by mean ± standard deviation,and categorical variables were expressed as number(N)and percentage(%).The distributions of continuous and categorical variables between patients with earlyonset preeclampsia and controls were compared by Pearson ?2 test or student t test.Concordance with Hardy-Weinberg equilibrium(HWE)was tested using standard?2 test or Fisher's exact test.Unconditional logistic regression analysis was used to evaluate the association between IL-10-1082A/G(rs-1800896),-819T/C(rs1800871),and-592A/C(rs 1800872)polymorphisms and risk of early-onset preeclampsia after adjustment for confounding factors,and the results were expressed as odds ratio(ORs)and corresponding 95%confience interval(95%CI).A twotailed P value of<0.05 was considered to be statistically signifiant.All of these statistical tests were done using Stata(version 10.0;StataCorp,College Station,TX)software programs.Results:Patients with early-onset preeclampsia were more likely to have higher BMI,systolic blood pressure and diastolic blood pressure,and have lower delivery week,infant birth weight and placenta weight,and receive more caesarean delivery,compared to the control subjects(P<0.05).there was signifiant difference in the observed genotype frequencies of IL-10-592A/C(rs 1800872)between patients with earlyonset preeclampsia and controls(?2 = 6.37,P =0.04).The results of the multivariate logistic regression analysis revealed that the association of individuals expressing the CC genotype and AC+CC of IL-10-592A/C(rs1800872)with asignifiantly increased risk of early-onset preeclampsia in co-dominant and dominant models,compared to the AA genotype;In the recessive model,we found that CC genotype of IL-10-592A/C(rs 1800872)was associated with the increased risk of early-onset preeclampsia when compared with AA+AC genotype.Conclusion:In our study,we investigated the association between gene polymorphisms and risk of earlyonset preeclampsia in North Chinese population.We found that the IL-10-592A/C(rs 1800872)polymorphism was associated with an increased risk of early-onset preeclampsia in North Inner Mongola Chinese population.In our study,we found an association between the expression of the CC genotype and AC+CC genotype of IL-10-592A/C(rs 1800872)and a signifiantly increased risk of early-onset preeclampsia compared to the AA genotype.