title: Inter and intra ethnic variation of vitamin K epoxide reductase complex and cytochrome P450 4F2 genetic polymorphisms and their prevalence in South Indian population.
abstract: BACKGROUND
  Genetic variation in the vitamin K epoxide reductase complex (VKORC1) and cytochrome P450 4F2 (CYP4F2) genes were found to be strongly associated with the oral anticoagulant (OA) dose requirement. The distribution of genetic variation in these two genes was found to show large inter- and intra-ethnic difference.
  
  
  METHODS
  A total of 470 unrelated, healthy volunteers of South Indians of either sex (age: 18-60 years) were enrolled for the study. A 5 ml of venous blood was collected and the genomic deoxyribonucleic acid (DNA) was extracted by using phenol-chloroform extraction method. Real-time quantitative polymerase chain reaction (RT-PCR) method was used for genotyping.
  
  
  RESULTS
  The variant allele frequencies of VKORC1 rs2359612 (T), rs8050894 (C), rs9934438 (T) and rs9923231 (A) were found to be 11.0%, 11.8%, 11.7% and 12.0%, respectively. The variant allele VKORC1 rs7294 was (80.1%) more frequent and the variant allele CYP4F2 * 3 was found to be 41.8% in South Indians. The allele, genotype and haplotype frequencies of VKORC1 and CYP4F2 gene were distinct from other compared HapMap populations (P < 0.0001).
  
  
  CONCLUSIONS
  The findings of our study provide the basic genetic information for further pharmacogenetic based investigation of OA therapy in the population.
authors: Department of Pharmacology, Indian Council of Medical Research Centre for Advance Research in Pharmacogenomics, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, India.
authors: Dhakchinamoorthi Krishna
authors: DK
authors: Kumar
authors: Deepak Gopal
authors: DG
authors: Shewade
authors: Sajjanavar
authors: S
authors: Manjunath
authors: Prayaga
authors: P
authors: Ushakiran
authors: Gangadharan
authors: G
authors: Reneega
authors: Chandrasekaran
authors: C
authors: Adithan
keywords: Cytochrome P450 4F2; South Indians; haplotypes; oral anticoagulants; vitamin K epoxide reductase complex