Distribution of ADH2 and ALDH2 genotypes in different populations

Abstract

The distribution of the human liver alcohol dehydrogenase, ADH2, and aldehyde dehydrogenase, ALDH2, genotypes in 21 different populations comprising Mongoloids, Caucasoids, and Negroids was determined by hybridization of the amplified genomic DNA with allele-specific oligonucleotide probes. Whereas the frequency of the ADH1(2) allele was found to be relatively high in the Caucasoids, Mexican Mestizos, Brazilian Indios, Swedish Lapps, Papua New Guineans and Negroids, the frequency of the ADH2(2) gene was considerably higher in the Mongoloids and Australian Aborigines. The atypical ALDH2 gene (ALDH2(2)) was found to be extremely rare in Caucasoids, Negroids, Papua New Guineans, Australian Aborigines and Aurocanians (South Chile). In contrast, this mutant gene was found to be widely prevalent among the Mongoloids. Individuals possessing the abnormal ALDH2 gene show alcohol-related sensitivity responses (e.g. facial flushing), have the tendency not to be habitual drinkers, and apparently suffer less from alcoholism and alcohol-related liver disease.

Interaction between alcohol dehydrogenase II gene, alcohol consumption, and risk for breast cancer

“…The ADH2-2 allele, which encodes the more active b2-subunit, is more prevalent in Asian populations (60 -80%) than Caucasians (0 -10%) (Goedde et al, 1992) and leads to an increased metabolic rate in vitro (9.2 min 71 for b1b1 and 400 min 71 for b2b2 isoenzymes) (Bosron and Li, 1986). Furthermore, the ADH2 polymorphism has been shown to increase the alcohol elimination rate after alcohol consumption (Thomasson et al, 1993) and to influence the metabolism of alcohol in peripheral tissues (Takeshita et al, 1996).…”

“…All ethidium bromide-stained fragments were analysed on a UV source using an image analysis system. The ADH2-2 allele of the polymorphism was defined as the presence of the MaeIII digestive site, according to a previous publication (Goedde et al, 1992).…”

ALDH2*2 and peer drinking in East Asian college students

“…One drink was equivalent to 14 grams of ethanol consumed (27). The frequency midpoints (shown in parenthesis), based on a month with 30 days, were never (0), monthly or less (0.5), 2 to 4 times a month (3), 2 to 3 times a week (10.7), and 4 or more times a week (23.54). The quantity midpoints (shown in parentheses) were 1–2 (1.5), 3–4 (3.5), 5–6 (5.5), 7–9 (8), and 10 or more (15.5) (27).…”

“…This is due in part to an allele (i.e., ALDH2 *2 or A-allele at rs671) more commonly carried by northeast Asians (30–50%) and rare in non-Asians (3). The ALDH2 *2 allele is linked to alcohol-related flushing, an adverse reaction to the metabolism of alcohol that includes reddening of the face, headaches, nausea, drowsiness, and abnormal heart beats (4,5).…”

Alcohol and coronary artery calcification: an investigation using alcohol flushing as an instrumental variable

“…Studies using genetic information as instrumental variables (IVs), such as Mendelian randomization studies, 8 have presented better evidence regarding the relationship between alcohol consumption and cardiovascular outcomes. [9][10][11][12][13][14] Among East Asians, including Chinese, Japanese, and Koreans, variants in the acetaldehyde dehydrogenase 2 (ALDH2) gene, which is responsible for the oxidation of acetaldehyde to acetate, are common, 15,16 and can be used as an IV for Mendelian randomization studies ( Supplementary Fig. 1).…”