Table 3 Epidemiologic studies of dopamine receptor gene (DRD4) and tobacco use in human populations.
From: Genetics of Tobacco Use
First Author, Year | Population, Sample size | Gene | Statistically Significant (p < 0.05) Results |
|---|---|---|---|
Luciano 2004 | Australia N = 769 single twins | DRD4 48-base pair repeat polymorphism | No significant association or linkage tests |
Hutchinson 2002 | USA N = 68 | DRD4 L/*avs. S/S | Interaction between genotype and response to smoking cues: DRD4 L/*, but not S/S, have increased craving, attention, arousal, and decreased positive affect during exposure to smoking cues |
| Â | Â | Â | No main effect of DRD4 on novelty seeking, nicotine dependence, smoking history or response to smoking cues. |
Lerman 1998 | USA N = 231 smokers | DRD4 L/* vs. S/S | Interaction between depression and genotype: depressed smokers with S/S are more likely to practice stimulation smoking and negative-affect reduction smoking; effect not seen in L/* genotypes |
| Â | Â | Â | No main effect of DRD4 on depression, stimulation smoking, negative-affect reduction smoking or nicotine dependence. |
Shields 1998 | USA N = 430 | DRD4 L/* vs. S/S | In African-Americans: L/* predicts increased smoking, shorter time to first cigarette in the morning and earlier age at smoking initiation. No L/* genotype smokers were abstinent 2 months after smoking cessation counseling, vs. 35% of S/S genotype smokers |
| Â | Â | Â | No significant association with genotype and smoking in Caucasians. |