Genetic polymorphism in CYP2E1: Population distribution of CYP2E1 activity

Neafsey, P; Ginsberg, G; Hattis, D; Johns, DO; Guyton, KZ; Sonawane, B

HERO ID

196814

Reference Type

Journal Article

Subtype

Review

Year

2009

Language

English

PMID

20183527

HERO ID 196814
Material Type Review
In Press No
Year 2009
Title Genetic polymorphism in CYP2E1: Population distribution of CYP2E1 activity
Authors Neafsey, P; Ginsberg, G; Hattis, D; Johns, DO; Guyton, KZ; Sonawane, B
Journal Journal of Toxicology and Environmental Health, Part B: Critical Reviews
Volume 12
Issue 5
Page Numbers 362-388
Abstract Cytochrome P-450 2E1 (CYP2E1) is a key enzyme in the metabolic activation of a variety of toxicants including nitrosamines, benzene, vinyl chloride, and halogenated solvents such as trichloroethylene. CYP2E1 is also one of the enzymes that metabolizes ethanol to acetaldehyde, and is induced by recent ethanol ingestion. There is evidence that interindividual variability in the expression and functional activity of this cytochrome (CYP) may be considerable. Genetic polymorphisms in CYP2E1 were identified and linked to altered susceptibility to hepatic cirrhosis induced by ethanol and esophageal and other cancers in some epidemiological studies. Therefore, it is important to evaluate how such polymorphisms affect CYP2E1 function and whether it is possible to construct a population distribution of CYP2E1 activity based upon the known effects of these polymorphisms and their frequency in the population. This analysis is part of the genetic polymorphism database project described in the lead article in this series and followed the approach described in that article (Ginsberg et al., 2009, this issue). Review of the literature found that there are a variety of CYP2E1 variant alleles but the functional significance of these variants is still unclear. Some, but not all, studies suggest that several upstream 5' flanking mutations affect gene expression and response to inducers such as ethanol or obesity. None of the coding-region variants consistently affects enzyme function. Part of the reason for conflicting evidence regarding genotype effect on phenotype may be due to the wide variety of exposures such as ethanol or dietary factors and physiological factors including body weight or diabetes that modulate CYP2E1 expression. In conclusion, evidence is too limited to support the development of a population distribution of CYP2E1 enzyme activity based upon genotypes. Health risk assessments may best rely upon data reporting interindividual variability in CYP2E1 function for input into physiologically based pharmacokinetic (PBPK) models involving CYP2E1 substrates.
Doi 10.1080/10937400903158359
Pmid 20183527
Wosid WOS:000271375100003
Url http://dx.doi.org/10.1080/10937400903158359
Is Certified Translation No
Dupe Override No
Comments Journal: Journal of Toxicology and Environmental Health, Part B: ISSN:
Is Public Yes
Language Text English
Keyword Pharmacy And Pharmacology; Polymorphism; Population genetics; Enzymes; Genotype & phenotype; Metabolism
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