Our findings indicate that the blood EtOH concentrations of ADH1B * 2 / * 2 group are higher than those of ADH1B * 1 / * 2 group regardless of ALDH2 genotype , and the blood acetaldehyde concentrations of ADH1B * 2 / * 2 are also higher than those of ADH1B * 1 / * 2 only in the ALDH2 * 1 / * 2 group .