title: [Association of the IL-18 gene polymorphism with susceptibility to colorectal cancer].
abstract: OBJECTIVE
  To investigate single nucleotide polymorphisms(SNPs) and haplotypes of interleukin-18(IL-18) gene associated with the susceptibility to colorectal cancer(CRC).
  
  
  METHODS
  Two SNPs of IL-18 gene promoter -137G/C and -607C/A in 170 patients with CRC and 160 healthy controls matched by age and sex in a Chinese population were analyzed using polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) strategy. Frequency of haplotypes and linkage disequilibrium of IL-18 gene in different groups were analyzed by SHEsis programs.
  
  
  RESULTS
  The distributions of IL-18 gene -607C/A polymorphism did not differ between CRC patients and healthy controls, but IL-18 gene -137G/C polymorphism was significantly different(P<0.05). The relative risk  of C allele for CRC was 1.814 times of the G allele (OR=1.814,95% CI:1.246-2.642). Consistent with the results of the genotyping analyses, IL-18 -137G/C and -607C/A polymorphisms showed strong linkage disequilibrium(|D'|=0.945), frequency of the -137C/-607A haplotype in patients with CRC was significantly higher than that in healthy controls(P<0.05). The -137C/-607A haplotype was associated with a significantly increased risk of CRC(OR=1.637, 95% CI:1.100-2.437).
  
  
  CONCLUSIONS
  IL-18 gene -137G/C polymorphism and -137C/-607A haplotype are associated with CRC. -137C allele may be an important genetic susceptibility gene for CRC.
authors.affiliation: Department of Coloproctology, Youjiang Medical College for Nationalities, Guangxi Baise, China. asdfghjkl1202002@163.com
authors.forename: Jun-yu
authors.initials: JY
authors.lastname: Guo
authors.forename: An-qiang
authors.initials: AQ
authors.lastname: Qin
authors.forename: Ru-kun
authors.initials: RK
authors.lastname: Li
authors.forename: Chang-mou
authors.initials: CM
authors.lastname: Yang
authors.forename: Fu-da
authors.initials: FD
authors.lastname: Huang
authors.forename: Zhan-yi
authors.initials: ZY
authors.lastname: Huang
authors.forename: Hou-ji
authors.initials: HJ
authors.lastname: Guo
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D006801:Humans; D020382:Interleukin-18 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide
chemical_list: D020382:Interleukin-18