Genetic Susceptibility to Esophageal Cancer due to CYP1A1 Gene Variant rs4646903 in Tobacco Addicted Patients of Pashtun Ethnicity: a Case Control Study in Khyber Pakhtunkhwa Province of Pakistan

  • Zakiullah, Zakiullah (Department of Pharmacy, Faculty of Life & Environmental Sciences, University of Peshawar) ;
  • Saeed, Muhammad (Department of Pharmacy, Faculty of Life & Environmental Sciences, University of Peshawar) ;
  • Ali, Sajid (Centre of Biotechnology & Microbiology, Faculty of Life & Environmental Sciences, University of Peshawar) ;
  • Javed, Nabila (Institute of Radiotherapy & Nuclear Medicine (IRNUM)) ;
  • Khisroon, Muhammad (Department of Zoology, Faculty of Life & Environmental Sciences, University of Peshawar) ;
  • Muhammad, Basir (Department of Clinical Oncology, BINOR Cancer Hospital) ;
  • Khuda, Fazli (Department of Pharmacy, Faculty of Life & Environmental Sciences, University of Peshawar) ;
  • Ahmad, Saeed (Department of Microbiology & Biotechnology, Faculty of Life & Environmental Sciences, Sarhad University of Science & Information Technology) ;
  • Ismail, Mohammad (Department of Pharmacy, Faculty of Life & Environmental Sciences, University of Peshawar)
  • Published : 2014.08.30


The purpose of this study was to evaluate associations of the CYP1A1 gene variant rs4646903 polymorphism with the risk of developing esophageal cancer (EC). A case-control study was carried out in Pashtun population of Khyber Pakhtunkhwa province of Pakistan in which 140 hospital based EC cases and 196 population based healthy controls exposed to similar environmental conditions were included. A specific method based on the real time polymerase chain reaction (RT-PCR) was used to detect genotypes in case and control groups and results were then analyzed with SPSS version 20. In our population, individuals with CC and TC genotypes of the CYP1A1 rs4646903 polymorphism had significantly higher risk of EC (adjusted odds (OR): 15.709, 95%CI: 6.065-40.686, OR: 3.256 95%CI: 1.902-5.574 respectively). The 'C' allele was strongly associated with the disease (p< 0.0001). Adjusted OR was higher (1.5 times in C/C) in case of variant alleles that show the contribution of environmental and nutritional factors towards the development of EC. Our findings suggest that presence of the 'C' allele of rs4646903 (T>C) may be one of the risk alleles for EC susceptibility in Pashtun population.


Esophageal cancer risk;CYP1A1 gene variant rs4646903;Pashtun population;Pakistan


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