Gene environment interaction in preterm delivery with special reference to organochlorine pesticide: a case control study.

OBJECTIVES: To assess the Gene-Environmental interaction between maternal organochlorine pesticides (OCPs) level and CYP17 gene polymorphism with the risk of preterm delivery (PTD).

MATERIALS AND METHODS: Maternal blood samples of hundred cases (n = 100) of PTD and of equal number of healthy controls were collected at the time of delivery. OCPs levels were estimated by Gas chromatography system equipped with electron capture detector and PCR-RFLP was used for polymorphic analysis of CYP17 gene.

RESULTS: Significantly (p < 0.05) higher levels of α-HCH, β-HCH, and γ-HCH were found in maternal blood samples of PTD cases as compared to controls. We did not found any significant difference in the frequency genotype distribution CYP17 gene in PTD cases as compared to controls. When gene environmental interaction between the CYP17 gene polymorphism and OCPs level was considered, a significant interaction was observed between ≥ 50th percentile of γ-HCH and CYP17 A1A1 (wild type) genotype.

CONCLUSIONS: Higher levels of OCPs along with wild type state of CYP17 gene (A1A1) in women may be considered as an important etiological factor in 'idiopathic' PTD. The present study provides evidence that genetic variation and its interaction with the environmental exposure may increase the risk of PTD.