A case-control study on the association between genetic polymorphisms of metabolic enzymes and the risk of colorectal cancer.
- Author:
Kun CHEN
1
;
Ming-juan JIN
;
Chun-hong FAN
;
Liang SONG
;
Qin-ting JIANG
;
Wei-ping YU
;
Xin-yuan MA
;
Kai-yan YAO
Author Information
- Publication Type:Journal Article
- MeSH: Alleles; Case-Control Studies; Colorectal Neoplasms; enzymology; genetics; Female; Genetic Predisposition to Disease; Genotype; Homozygote; Humans; Male; Middle Aged; Polymorphism, Genetic
- From:Chinese Journal of Epidemiology 2005;26(9):659-664
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the association between metabolic enzymes polymorphisms and the risk of colorectal cancer(CRC).
METHODSMethods of detection used were based on polymerase chain reaction(PCR) including PCR-restriction fragment length polymorphism (PCR-RFLP), allele specific-PCR (AS-PCR) and multiple-PCR to identify the polymorphisms of CYP1A1 6235T/C, CYP1A2 734C/A, CYP2E1 -1259G/C, CYP2E1 -1019C/T, GSTM1 and T1 null type, NAT1 and NAT2 alleles among 140 cases and 343 cancer-free controls.
RESULTSThe allele frequencies of CYP1A1 6235C, CYP1A2 734A, CYP2E1 -1259C, CYP2E1 -1019T, GSTM1 and T1 null type, NAT1* 10 and NAT2 Mx (x = 1,2,3) alleles were 31.65%, 63.77%, 23.02%, 32.61%, 57.25%, 17.39%, 26.45% and 39.21% in the case group and 39.85%, 66.62%, 20.27%, 28.61%, 55.46%, 20.35%, 25.22% and 39.36% in control group, respectively. The frequencies were in Hardy-Weinberg equilibrium. Data on single genetic polymorphism and stratification analysis of multi-genetic polymorphisms indicated that CYP1A1 6235CC homozygote was associated with the significant reduction of CRC risk (OR = 0.79, 95% CI: 0.63-0.99) and in individuals with CYP1A2 734A allele. CYP1A1 62345C allele had the same effect (OR = 0.53, 95% CI: 0.34-0.83). However, individuals with GSTT1 null genotype, GSTM1 null genotype could significantly increase the risk (OR = 4.41, 95% CI: 1.21-16.10).
CONCLUSIONCYP1A1 6235C allele might play an important role in fighting against colorectal carcinogenesis. However, GSTM1 and T1 null genotype might serve as risk factors genetically. Larger scale population-based studies were needed to confirm the current findings.