Specific personality traits and dopamine, serotonin genes in anxiety-depressive alcoholism among Han Chinese in Taiwan.
BACKGROUND
Cloninger [Cloninger CR. 1987. Neurogenetic adaptive mechanisms in alcoholism. Science 236: 410-416.] had proposed a psychobiological model suggesting that three main personality dimensions distinguish the alcoholism into two subtypes (type I and type II). However, the classification was equivocal for clinical diagnosis. Recently, anxiety-depressive alcohol dependence (ANX/DEP ALC) has been posited as a genetically specific subtype of alcoholism. Its clinical characteristics were similar to individuals with type I alcoholism [Cloninger, C.R. 1987. Neurogenetic adaptive mechanisms in alcoholism. Science 236: 410-6.] such as having a high comorbidity with mood disorder, late-onset and more anxious/depressed traits. We attempted to investigate whether the dopamine D2 receptor (DRD2) and the serotonin transporter promoter region (5-HTTLPR) genes were involved in Novelty Seeking (NS) and Harm Avoidance (HA) of ANX/DEP ALC.


METHODS
We recruited 46 pure alcohol dependents (Pure ALC) and 87 anxiety-depression alcohol dependents (ANX/DEP ALC). All participants were diagnosed by DSM-IV criteria, genotyped by the PCR method and assessed with Tridimensional Personality Questionnaire (TPQ).


RESULTS
Both NS and HA were high in ANX/DEP ALC (p = 0.021; p = 0.001, respectively). The association between NS and ANX/DEP ALC only existed in subjects with DRD2 TaqI A1(+) allele (A1/A1 or A1/A2 genotypes) (p = 0.004) and in those with S/S genotype of 5-HTTLPR (p = 0.005). With the stratification of DRD2 TaqI A1(+) allele, high NS of ANX/DEP ALC existed only in carriers of 5-HTTLPR S/S genotype (p=0.001). Moreover, ANX/DEP ALC was related to high HA only in samples carrying 5-HTTLPR S/L or L/L genotype (p = 0.02).


CONCLUSIONS
These findings provided the empirical genetic characterization of the specific personality traits in ANX/DEP ALC among Han Chinese population in Taiwan.
Lin
Shu-Cheng
SC
Institute of Behavioral Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan, ROC.
Wu
Pei-Lin
PL
Ko
Huei-Chen
HC
Wu
Jo Yung-Wei
JY
Huang
San-Yuan
SY
Lin
Wei-Wen
WW
Lu
Ru-Band
RB
D000328:Adult; D000437:Alcoholism / Q000453:epidemiology / Q000235:genetics* / Q000523:psychology*; D001007:Anxiety / Q000453:epidemiology / Q000235:genetics* / Q000523:psychology*; D004247:DNA / Q000097:blood / Q000235:genetics; D003863:Depression / Q000453:epidemiology / Q000235:genetics* / Q000523:psychology*; D005106:Exploratory Behavior; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D010551:Personality / Q000235:genetics*; D010556:Personality Tests; D011110:Polymorphism, Genetic / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D013624:Taiwan / Q000453:epidemiology
D017448:Receptors, Dopamine D2; D050486:Serotonin Plasma Membrane Transport Proteins; D004247:DNA