Prognostic role of Interluekin-1 α and β gene polymorphisms in preterm birth

Abstract

Background Increasing evidence supports a role for pro-inflammatory cytokine IL-1 gene in preterm birth. Aim The aim of this study is to assess the role of IL-1 with the risk of preterm birth. Subjects and Methods This case-control study was conducted in King George's Medical University, a tertiary care hospital. Cases (n = 559) were defined as mothers (age 18-40 y) of singleton live preterm. Controls (n = 559) were mothers who delivered a singleton neonate, consecutive to enrolled case, after completing 37 weeks of gestation. Four polymorphisms of (IL1α - 889C/T, + 4845C/T) and IL1β genes (- 31T/C and - 511C/T) were typed from genomic DNA. Allelic frequencies were compared between cases and control subjects and haplotypic analysis was carried out. Results Haplotype analysis demonstrated significant association between preterm birth and genotypes frequency of both the genes (p < 0.05). Significant association was found in CT haplotype (OR = 1.36, 95%CI (1.14-1.62), p ≤ 0.001) of first block and CT (OR = 1.29, 95% CI (1.01-1.64), p = 0.039) and TT (OR = 1.20, 95% CI (1.00-1.43), p = 0.044) haplotype of second block. We observed higher frequency of IL-1 haplotype distribution (CTTC, CTTT, TTCT, CCTC and CCCT) among cases (P = 0.03-0.001, OR = 1.57-1.97). Conclusions Our findings suggest that the polymorphisms and haplotypes in the IL1 gene contribute as a risk factor to PTB in North Indian population.