Genetic polymorphisms in Cytochrome P 4501B1 and susceptibility to idiopathic preterm labor in North Indian population

• CYP1B1 gene is involved in estrogen hormone synthesis and xenobiotic metabolism.
• Homozygous variant of CYP1B1*2 was significantly higher in PTL cases.
• Heterozygous variant of CYP1B1*3 and CYP1B1*7 genes were significantly higher in PTL cases.
• CYP1B1 gene polymorphism have shown the genetic susceptibility to PTL.

ObjectiveThe etiology of preterm labor (PTL) is still unknown, but it may be related to a possible genetic predisposition together with involvement of environmental factors. We investigated the relation between PTL and polymorphisms in Cytochrome P4501B1 (CYP1B1) gene, which is involved in the metabolism of a wide range of environmental toxins and hormones.Design and methodsThree hundred (n = 300) cases of PTL and equal number of subjects of full term labor (FTL), after excluding all the known risk factors for PTL were included in the study. A two step allele specific PCR was performed for polymorphic analysis of CYP1B1 gene.ResultsThe homozygous variant genotype of CYP1B1*2 (OR = 2.97, 95%CI = 1.08–8.08, p = 0.033) and heterozygous variant of CYP1B1*3 (OR = 2.57, 95%CI = 1.88–3.63, p = 0.001), and CYP1B1*7 (OR = 2.59, 95%CI = 1.85–3.62, p = 0.001) were found to be significantly higher in PTL cases as compared to FTL.ConclusionsThe present study demonstrates the possible association of homozygous variant of CYP1B1*2 and heterozygous variant of CYP1B1*3 and CYP1B1*7 genes with the increased risk of PTL.