title: Genetic Variations inLeptin andLeptin Receptor and Susceptibility to Colorectal Cancer and Obesity.
abstract: BACKGROUND
  Colorectal cancer (CRC) is the second most commonly diagnosed cancer and the fourth leading cause of cancer-related mortality around the world.
  
  
  OBJECTIVE
  With regard to the role of obesity in colorectal cancer (CRC) and the role ofleptin in obesity, we investigated whetherleptin(LEP) andleptinreceptor (LEPR) gene variants are associated with CRC risk.
  
  
  METHODS
  We evaluatedLEP(rs7799039) andLEPR(rs1137101) gene variants by using PCR-RFLP method in 261 cases with CRC and 339 controls.
  
  
  RESULTS
  No significant difference was found for rs7799039 and rs1137101gene variants between the cases with CRC and controls. However, theLEPRrs1137101 "GG" genotype compared with "AA" genotype and "AA + AG" genotype was associated with increased risks for obesity, and the differences remained significant after adjustment for confounding factors including age, sex, smoking status, and NSAID use (P = 0.015; OR = 2.42, 95%CI = 1.19 - 4.93 and P = 0.016; OR = 2.28, 95%CI = 1.17 - 4.48, respectively). In addition, theLEPR"G" allele compared with the "A" allele was associated with an increased risk for obesity (P = 0.024; OR = 1.44, 95%CI = 1.05 - 1.98).
  
  
  CONCLUSIONS
  Consistent with most previous studies, our findings found no association betweenLEP(rs7799039) andLEPR(rs1137101) gene variants and CRC risk. However, theLEPRrs1137101 "GG" genotype compared with the "AA" genotype and "AA+AG" genotype was associated with a 2.42-fold and a 2.28-fold increased risk for obesity, respectively.
authors.affiliation: Department of Cancer, Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Touraj
authors.initials: T
authors.lastname: Mahmoudi
authors.affiliation: Department of Physiology, School of Medicine, Qom University of Medical Sciences, Qom, IR Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Farahani
authors.affiliation: Internal Medicine Department, Semnan University of Medical Sciences, Semnan, IR Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Nobakht
authors.affiliation: Internal Medicine Department, Semnan University of Medical Sciences, Semnan, IR Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Dabiri
authors.affiliation: Department of Cancer, Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Zali
keywords: Colorectal Cancer; LEP; LEPR; Variant