Abstract
Microsomal epoxide hydrolase is a smooth endoplasmic reticulum enzyme and is expressed relatively ubiquitously in most tissues and in many species. The microsomal epoxide hydrolase (mEH) encoded by EPHX1 is a biotransformation enzyme that metabolizes numerous reactive epoxide intermediates to more water-soluble trans-dihydrodiol derivatives. In the present study, we genotyped two SNPs of the EPHX1 gene [(Exon 3: Tyr113His; rs1051740) and (Exon 4: His139 Arg; rs2234922)], using TaqMan allelic discrimination among 212 individuals of six major south Indian populations, and compared with other available world populations data. Both polymorphisms followed Hardy-Weinberg equilibrium and were highly polymorphic in the studied populations. The haplotype based analysis revealed remarkable variation among the study populations. Linkage disequilibrium (LD) between Tyr113 His and His139Arg loci was not significant in any of the population studied. Calculation of LD in the 20kb up and downstream regions from Tyr113His and His 139Arg loci in HapMap populations revealed no significant LD between these markers in all the populations. Analysis of predicted EPHX1 activity status of all samples revealed that the prevalence of low activity samples is more than the intermediate and high activity samples in all populations studied. Screening of additional populations and computation of genetic distances between populations at SNP sites may help in understanding the population genetic and evolutionary aspects of this gene.
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Lakkakula, S., Maram, R., Munirajan, A.K. et al. EPHX1 gene polymorphisms among south Indian populations. Mol. Cell. Toxicol. 9, 219–225 (2013). https://doi.org/10.1007/s13273-013-0028-x
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DOI: https://doi.org/10.1007/s13273-013-0028-x