Association of VNTR polymorphisms in the MAOA promoter and DRD4 exon 3 with heroin dependence in male Chinese addicts.
OBJECTIVE
To explore the involvement of variable number tandem repeat (VNTR) polymorphisms in the monoamine oxidase A (MAOA) promoter and exon 3 of the dopamine D4 receptor (DRD4) gene in heroin addiction modulate the vulnerability of individuals to heroin addiction.


METHODS
Eight hundred and ninety-four male heroin addicts without other psychiatric disorders, were recruited as subjects. Another community 180 males were selected randomly as controls.


RESULTS
The geno-distribution of the DRD4 exon 3 VNTR polymorphism in controls was in Hardy-Weinberg equilibrium (HWEchi(2)=0.925), but the distribution in heroin addicts was not (HWEchi(2)=28.35). The long-repeat alleles of the DRD4 exon 3 VNTR polymorphism were found more frequently in the heroin addicts (P=0.019). However, the long-repeat alleles of the MAOA promoter VNTR polymorphism were not (P=0.828). No interaction between these two VNTR polymorphisms was found by using multiple logistic regression analysis (P=0.261).


CONCLUSIONS
The long-repeat allelic variants (>4-repeats) and 2-repeat allele of the DRD4 exon 3 VNTR polymorphism might be risk alleles for individual vulnerability to heroin addiction in Chinese men, but the MAOA promoter VNTR polymorphism does not mean that the partial dominant inherited mode might involved in the genetics of heroin dependence.
Chien
Chia-Chang
CC
Department of Psychiatry, Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan.
Lin
Chi-Hung
CH
Chang
Yong-Yuan
YY
Lung
For-Wey
FW
D000328:Adult; D000483:Alleles; D044466:Asian People / Q000235:genetics; D016022:Case-Control Studies; D005091:Exons / Q000235:genetics; D005838:Genotype; D006556:Heroin Dependence / Q000235:genetics*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D013624:Taiwan
C493599:DRD4 protein, human; D050638:Receptors, Dopamine D4