Abstract: Objective To explore the correlation between gene polymorphism of acetaldehyde dehydrogenase 2 （ALDH2） and drinking features as well as disease onset in patients with alcoholic liver disease （ALD）. Methods TaqMan fluorescent quantitation PCR was used for detecting gene polymorphism of ALDH2 in 296 unrelated healthy controls（HC） and 221 patients with ALD. The correlation between the ALDH2 gene polymorphism and the drinking features as well as disease onset of patients with ALD was analyzed. Results Mutation frequency of ALDH2 in recruited HC was 31.1% （92/296），which was far higher than that of almost zero in Europe，America，Africa and other countries（almost zero），and slightly higher than that of 22% in Asia （22%）. The genotype frequency of ALDH2*1/*1 in ALD group was significantly higher than that in HC group [93.7% （207/221） vs 69.0% （204/296），OR=6.668，P<0.0001] and the genotype frequency of allele ALDH2*1 in ALD group was also significantly higher than that in HC group[96.8% （428/442） vs 82.9% （491/592），OR=6.289，P<0.0001]. ALD group had lower genotype frequency of ALDH2*1/*2，ALDH2*2/*2 and allele ALDH2*2 than those of HC group [6.3% （14/221） vs 28.0% （83/296），OR=0.174，P<0.0001；0%（0/221） vs 3.0% （9/296）， OR=0.13，P<0.05；3.2% （14/442） vs 17.1%（101/592），OR=0.159，P<0.01]. There was no significant difference in distributive characteristics of gene polymorphism of ALDH2 at various stages of ALD development. Compared with those who carried ALDH2*1/*1，drinkers who carried ALDH2*2 were likely to develop ALD with less alcohol consumption （P<0.05）. Conclusions Allele ALDH2*1 was one of the risk factors for the development of ALD in drinkers，but only in condition of heavy and long-term drinking. Allele ALDH2*2 could“protect” human from developing ALD，however，drinkers with allele ALDH2*2 might develop ALD with less alcohol consumption and shorter drinking history.

Key words: ALDH2, Gene polymorphism, Alcoholic liver disease, Drinking features