Effect of maternal Tp53 gene G412C polymorphism on neural tube defects: A study from North India.

ABSTRACT

Context Tumor protein 53 (tp53) is one of the candidate gene proposed for neural tube defects, which affects central nervous system during early embryonic development, on the basis of mouse models. Aims: The present study is an attempt to unfold the possible role of tp53 G412C polymorphism in the incidence of neural tube defect (NTDs) in humans. Settings and Design: Case-control study was carried out in government hospitals of Delhi, India. Materials and Methods: Subjects comprised of 100 mothers of NTD children and 100 matched control mothers. Information on some environmental exposures was collected along with blood samples. After DNA extraction, the genotyping of tp53 G412C polymorphism was carried out by PCR-RFLP method. Statistical Analysys Fisher Exact or Chi square test, binary logistic model, and odds ratio (95% confidence interval) calculations were used to evaluate effect of risk factors on NTDs using SPSS v17.0. Results: The 'CC' genotype of tp53 G412C showed protective effect towards the development of anencephaly and/or encephalocele (OR 0.44; 95% CI 0.19-1.00); however, no significant difference among overall NTD cases and controls was observed (P>0.05). Further segregation of all subjects based on 2 different communities, Hindus and Muslims, the association of 'CC' genotype of the polymorphism with reduced NTD risk was observed among Hindu community (OR 0.33; 95% CI 0.13-0.79). Conclusion: The study highlights the selective advantage provided by maternal 'CC' genotype, thereby reducing risk of cephalic NTDs, probably due to the lower apoptotic activity of the protein, however, more specifically in the presence of community-specific microenvironment.