D2 dopamine receptor gene haplotypes and their influence on alcohol and tobacco consumption magnitude in alcohol-dependent individuals
Alcohol and Alcoholism 2007 42(3):258-266





Alcohol dependence and habitual smoking frequently co-occur and possibly mutually influence each other. Both have been related to alterations of dopaminergic neurotransmission.

The aim of this analysis of the Munich Gene Data Bank for Alcoholism(MGBA) was to re-evaluate the potential relation between D2 receptor and dopamine transporter gene haplotypes and quantity-related phenotypes of alcohol consumption (average daily alcohol intake before admission for treatment) and smoking (average units smoked per day).

Strong drinkers reported significantly higher amounts of smoking and vice versa. While no association was detected for dopamine transporter genetic variants, a number of D2 receptor gene single nucleotide polymorphisms were related to both smoking- and drinking-related behaviours.

Subsequent analysis of D2 receptor gene haplotypes revealed that two common haplotypes had a significant association with quantitative phenotypes of regular drinking (Ins-C-G-C-A1) and smoking (Ins-T-G-A-A2).

The finding of an association between common D2 dopamine receptor gene haplotypes with the quantity of drinking and smoking corroborates with results from previous studies suggesting a relationship between the dopamine system and alcohol and substance use disorders.

Furthermore, it makes D2 dopamine receptor a candidate gene significantly influencing both alcohol and nicotine dependence.


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Reprint Request E-mail: ulrich.preuss@medizin.uni-halle.de
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