RESUMEN
OBJECTIVES: We hypothesized that polymorphisms of ADH1B and NQO2 could have an effect on the onset of alcohol dependence and withdrawal symptoms. METHODS: PCR (polymerase chain reaction) and RFLP (restriction fragment length polymorphism) were used to analyze genetic polymorphisms of ADH1B and NQO2 in 194 male patients with alcohol dependence (AD) and 152 healthy comparisons. The AD were classified into the early and late onset groups with the onset age of 25. Alcohol withdrawal symptoms were measured by Clinical Institute Withdrawal Assessment for Alcohol Scale (CIWA-Ar). RESULTS: 1) Alcohol dehydrogenase 1B gene : There was no difference in genotype distribution between the patients group and the control group. However, the frequency of ADH1B*2 allele in late-onset alcohol dependence was higher compared to the early-onset group. 2) NRH-quinone oxidoreductase 2 (NQO2) : The patients group had higher frequency of D allele than the healthy comparisons. In patients group, the frequency of the D allele in the late-onset group was higher than the early-onset group. 3) CIWA-Ar scale : There was no difference in the CIWA-Ar scale between the genetic polymorphisms of ADH1B. However, the patients with D allele of NQO2 showed significantly higher scores in the CIWA-Ar scale than those with I/I allele. CONCLUSION: With current results, we suggested that ADH1B*2 and D allele of NQO2 may have a possible association with alcohol withdrawal symptoms and that they may play a protective role in the onset of alcohol dependence.