Evolution of the DRD2 gene haplotype and its association with alcoholism in Mexican Americans

Huai Rong Luo, Zhen Fang Hou, Julia Wu, Ya Ping Zhang, Yu-Jui Yvonne Wan

Research output: Contribution to journalArticlepeer-review

18 Scopus citations


The human D2 dopamine receptor gene (DRD2) plays a central role in the neuromodulation of appetitive behaviors and is implicated in having a possible role in susceptibility to alcoholism. We genotyped an SNP in DRD2 Exon 8 in 251 nonalcoholic, unrelated, healthy controls and 200 alcoholic Mexican Americans. The DRD2 haplotypes were analyzed using the Exon 8 genotype in combination with five other SNP genotypes, which were obtained from our previous study. The ancestral origins of the DRD2 polymorphisms have been determined by sequencing the homologous region in other higher primates. Twenty DRD2 haplotypes, defined as H1 to H20 based on their frequency from high to low, were obtained in this major minority population. The ancestral haplotype "I-B2-G-C-G-A1" and two one-step mutation haplotypes were absent in our study population. The haplotype H1, "I-B1-T-C-A-A1", with the highest frequency in the population, is a three-step mutation from the ancestral form. The first five or eight major haplotypes make up 87% or 95% of the entire population, respectively. The prevalence of the haplotype H1+ (H1/H1 and H1/Hn genotypes) is significantly higher in alcoholics and alcoholic subgroups, including early onset drinkers and benders, than in their respective control groups. The Promoter -141C allele is in linkage disequilibrium (LD) with five other loci in the nonalcoholic group, but not in the alcoholic group. All of the other five loci are in LD in both the alcoholic and control groups. The DRD2 TaqI B allele is in complete LD with the allele located in intron 6. Five SNPs, Promoter -141C, TaqI B (or Intron 6), Exon 7, Exon 8, and TaqI A, are sufficient to define the DRD2 haplotypes in Mexican Americans. Our data indicate that the DRD2 haplotypes are associated with alcoholism in Mexican Americans.

Original languageEnglish (US)
Pages (from-to)117-125
Number of pages9
Issue number2
StatePublished - Jun 2005
Externally publishedYes


  • Alcoholism
  • D2 dopamine receptor DRD2
  • Genotype
  • Haplotype
  • Mexican Americans
  • SNP

ASJC Scopus subject areas

  • Biochemistry
  • Medicine(all)
  • Behavioral Neuroscience
  • Neuroscience(all)
  • Toxicology
  • Health(social science)


Dive into the research topics of 'Evolution of the DRD2 gene haplotype and its association with alcoholism in Mexican Americans'. Together they form a unique fingerprint.

Cite this