Biological Study of Alcohol Dependence Syndrome with Reference to Ethnic Difference: Report of a WHO Collaborative Study

Abstract

Summary: Inherited deficiency of acetaldehyde dehydrogenase type I (ALDH‐I) was found in 43% (50/117) of normals, 33% (27/82) of schizophrenics, but only 4% (5/113) of alcoholics among Japanese. The ALDH‐I deficiency was never found, however, in 146 mostly schizophrenic subjects from Europe (Basel, Moscow, Zagreb), Australia (Nedlands), India (Lucknow), Morocco (Casablanca) and Mexico (Mexico City). It was demonstrated that ALDH‐I deficiency produces the flushing syndrome which inhibits the development of drinking habit and alcohol dependence syndrome.

Distribution of ADH2 and ALDH2 genotypes in different populations

“…In addition, the present study reports, for the first time, the distribution of the genotypes for the ADH2 and ALDH2 alleles (homozygote normal, heterozygote, and homozygote atypical) in a large num- Although the majority of the flushers were genotypically atypical for the ALDH2 loci, the atypical ADHz z gene may also account for some of the flushing cases, as suggested by Thomasson et al (1990). A markedly lower incidence of ALDH2 isozyme abnormality has been observed in alcoholics than in psychiatric patients, drug dependents and healthy controls in Japan, China, Korea, and Taiwan (Harada et al 1985;Yeh et al 1989;Yamashita et al 1990;Hwu et al 1991). Moreover, a significantly lower number of patients with alcoholic liver disease have the ALDH2 deficiency gene (Shibuya and Yoshida 1988).…”

Molecular Genetics of Substance Abuse Vulnerability: Remarkable Recent Convergence of Genome Scan Results

“…The allelic variations that have been most strongly associated with differential vulnerability to addiction are the striking variants in the alcohol and acetaldehyde dehydrogenase genes that produce flushing when alcohol is consumed. 40 These flushing syndrome variants exert a striking protective effect from alcoholism in the Asian populations in which these variants are common, but provide little impact in U.S. and other Caucasian populations in which these allelic variants are quite rare. 40 Substance abusers have diagnoses of depression, antisocial personality disorder/conduct disorder, and perhaps even adult residua of attention deficit/hyperactivity disorder much more frequently than control populations.…”

“…40 These flushing syndrome variants exert a striking protective effect from alcoholism in the Asian populations in which these variants are common, but provide little impact in U.S. and other Caucasian populations in which these allelic variants are quite rare. 40 Substance abusers have diagnoses of depression, antisocial personality disorder/conduct disorder, and perhaps even adult residua of attention deficit/hyperactivity disorder much more frequently than control populations. 18,22 Each of these diagnoses is likely to display heritable components.…”