Self-reported flushing and genotypes of ALDH2, ADH2, and ADH3 among Taiwanese Han.

The aims of this study are to investigate whether self-reported facial flushing postalcohol consumption (PAC) among subjects with ALDH21/1 can be attributed to ADH2 or ADH3 and whether the prediction of ALDH2 genotype can be improved by examining the combination of flushing and other accompanying reactions of PAC sensitivity. Fifty-eight subjects of Han ancestry in Taiwan were interviewed for alcohol-sensitivity reactions and their blood samples were genotyped for ALDH2, ADH2, and ADH3. For subjects with ALDH21/1 (n = 46), 70% reported to have no flushing PAC and 30% reported flushing PAC. When subjects with ALDH21/1 had ADH21/1 (n = 11), all reported to have no flushing; otherwise, 35% (for ADH21/2, n = 17) and 44% (for ADH22/2, n = 18) reported flushing. For subjects with ALDH21/1 and at least one ADH22 allele, the genotype of ADH3 was not associated with self-reported flushing. PAC flushers with ALDH21/1 (50%) were more likely to report nausea than those with ALDH21/2 (8%). The probability of ALDH21/1 given flushing reported was 0.29, while the probability of ALDH21/*1 given both flushing and nausea reported was 0.71. The results indicate that self-reported flushing is determined by both ALDH2 and ADH2 and that prediction of ALDH2 genotype on the basis of self-reported flushing and nausea can help identify subjects at increased risk for alcoholism.