Background/Aims: Genetic susceptibility to chemical carcinogens is one of the most important hos
factors in human cancers. The genetically determined differences in metabolism related to cytochrome
P450 (CYP450) and glutathione S-transferases (GSTs)...
Background/Aims: Genetic susceptibility to chemical carcinogens is one of the most important hos
factors in human cancers. The genetically determined differences in metabolism related to cytochrome
P450 (CYP450) and glutathione S-transferases (GSTs) genes have been reported to be associated with
various cancer susceptibility. This study was undertaken to reveal the association of the polymor
phism of the cytochrome P450 (CYP1A1/MspI) and the glutathione S-transferases isozymes (GST-mu
and GST-theta) with the genetic susceptibility of gastric cancer development in Koreans. Methods:
In this study, 85 patients with stomach cancer and 107 controls were analysed using polymerase chain
reaction-restriction fragment polymorphisms (PCR-RFLPs). Results: In the analysis of CYP1A1/MspI polymorphism, the overall genotype distribution was not statistically different between the patients and controls. The genotype of m1/m2 was highly detected in patients with cardia cancer and early gastric cancer and patients under the age of 45. In the analysis of glutathione S-transferases isozyme
(GST-mu and GST-theta), there were no statistical differences between the distribution of genotypes
of the patients and the controls. The frequency of the null genotypes was relatively higher in patient
with no smoking history than in those with smoking history, but statistically not significant Conclusions: The polymorphisms of the CYP1A1 and glutathione S-transferases isozyme (GST-mu and GST-theta) genes may not be important factors in determining the genetic susceptibility to stomach cancer development in Koreans. To discover potential associations between the genotypes of these genes and stomach cancer susceptibility, it is necessary to evaluate the polymorphisms in othe ethnic groups and to analyse more patients in the future. (Kor J Gastroenterol 1999;33:27 - 37)