title: Allele frequencies of the preproenkephalin A (PENK) gene CA repeat in Asians, African-Americans, and Caucasians: lack of evidence for different allele frequencies in alcoholics.
abstract: Evidence from animal models and from recent reports on the efficacy of the opioid antagonist naltrexone in the treatment of alcoholism suggests that the endogenous opioid systems may play a role in alcohol seeking behavior. The gene encoding preproenkephalin A (PENK) is flanked at its 3' end by a polymorphic (CA)n repeat. We determined the allele frequencies for this locus in samples of Chinese and Atayal living in Taiwan, Caucasians living in the United States and Byelorussia, and African-Americans living in the United States. We compared the allele frequencies of nonalcoholics in each population with those of alcoholics with or without alcohol-induced organ pathology. There was no difference in allele frequencies within any racial group when alcoholics with or without organ pathology were compared; there was also no difference in allele frequency between nonalcoholics and alcoholics within the two Asian populations, Caucasians, or African-Americans. There were highly significant differences in the frequency of the various length polymorphisms between the Asian, Caucasian, and African-American samples.
authors.affiliation: Department of Medicine, Indiana University School of Medicine, Indianapolis.
authors.forename: R J
authors.initials: RJ
authors.lastname: Chan
authors.forename: A W
authors.initials: AW
authors.lastname: McBride
authors.forename: H R
authors.initials: HR
authors.lastname: Thomasson
authors.forename: A
authors.initials: A
authors.lastname: Ykenney
authors.forename: D W
authors.initials: DW
authors.lastname: Crabb
mesh_terms: D000437:Alcoholism / Q000235:genetics* / Q000473:pathology; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D044383:Black People / Q000235:genetics*; D002681:China; D002874:Chromosome Mapping; D015331:Cohort Studies; D003431:Cross-Cultural Comparison; D004745:Enkephalins / Q000235:genetics*; D005787:Gene Frequency; D005828:Genetics, Population; D006801:Humans; D008099:Liver / Q000473:pathology; D008108:Liver Diseases, Alcoholic / Q000235:genetics* / Q000473:pathology; D012150:Polymorphism, Restriction Fragment Length; D011498:Protein Precursors / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D014481:United States; D044465:White People / Q000235:genetics*; D001741:Black or African American
chemical_list: D004745:Enkephalins; D011498:Protein Precursors; C033660:preproenkephalin