title: Ethnic differences in the prevalence of the homozygous deleted genotype of glutathione S-transferase theta.
abstract: In humans the glutathione S-transferase (GST) genes encode four classes of proteins (GST) important in the detoxification of reactive electrophiles. Recently, a gene deletion polymorphism was discovered within the GST class theta locus that leads to a functional deficiency in GST theta activity within circulating red blood cells. In this study we have examined the ethnic distribution of this polymorphism using a polymerase chain reaction (PCR)-based genotyping method. Five different ethnic groups were studied: North American Caucasians, African-Americans, Mexican-Americans, Chinese and Koreans. The prevalence of the null genotype was highest among Chinese (64.4%), followed by Koreans (60.2%), African-Americans (21.8%) and Caucasians (20.4%), whereas the prevalence was lowest among Mexican-Americans (9.7%). Interestingly, the prevalence of the deleted genotype in Caucasians differed significantly when 257 individuals drawn from a nation wide organization were compared with 185 people from the New England area (23.7 versus 15.7%, P < 0.05, chi 2 test). These results indicate that there are major differences in the prevalence of this trait attributable to ethnicity and that ethnic origin even among Caucasians should be considered in studies of gene-environment interaction involving this polymorphism.
authors.affiliation: Department of Cancer Biology, Harvard School of Public Health, Boston MA 02115 USA.
authors.forename: H H
authors.initials: HH
authors.lastname: Nelson
authors.forename: J K
authors.initials: JK
authors.lastname: Wiencke
authors.forename: D C
authors.initials: DC
authors.lastname: Christiani
authors.forename: T J
authors.initials: TJ
authors.lastname: Cheng
authors.forename: Z F
authors.initials: ZF
authors.lastname: Zuo
authors.forename: B S
authors.initials: BS
authors.lastname: Schwartz
authors.forename: B K
authors.initials: BK
authors.lastname: Lee
authors.forename: M R
authors.initials: MR
authors.lastname: Spitz
authors.forename: M
authors.initials: M
authors.lastname: Wang
authors.forename: X
authors.initials: X
authors.lastname: Xu
mesh_terms: D044466:Asian People / Q000235:genetics; D001483:Base Sequence; D044383:Black People / Q000235:genetics; D002681:China / Q000208:ethnology; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D017931:DNA Primers; D005006:Ethnicity / Q000235:genetics*; D017353:Gene Deletion; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006630:Hispanic or Latino; D006720:Homozygote; D006801:Humans; D007527:Isoenzymes / Q000235:genetics*; D007723:Korea / Q000208:ethnology; D008800:Mexico / Q000208:ethnology; D008969:Molecular Sequence Data; D009511:New England; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D044465:White People / Q000235:genetics; D001741:Black or African American
chemical_list: D017931:DNA Primers; D007527:Isoenzymes; D003577:Cytochrome P-450 Enzyme System; D005982:Glutathione Transferase