There are seven mutations observed in different ethnicities with higher relative prevalence, there is more cancer issued mutations[3]. Most studied of them is East Asian mutation (ALDH2*2) connected with alcohol flushing syndrome and other diseases[2]. ALDH2*2 alcohol flushing response is semidominant, thus heterozygotic individuals show lesser phenotype. After moderate consumption of alcohol, individuals affected by alcohol suffer from heavier hangover symptoms, homozygotes, even extreme one such as tachycardia, hypotension, nausea, and vomiting. Heterozygotes have reported subjectively more intense and more pleasant rection to alcohol than individuals with ALDH2*1/2*1[4]. There are fewer people with at least one copy of ALDH2*2 who suffer from liver cirrhosis, thus is concluded that this mutation can serve as protection against excessive alcohol consumption. This fact depends on cultural differences and relationship with alcohol as the protective effect is somehow weaker in African or European populations, as there can be social pressure to drink more alcohol in social activities, even in Eastern cultures people with flushing cannot escape or reject such alcoholism[5].
| ALDH2 designation
| Mutation
| Location
| AA change
| Major ethnicity
| Allele frequency
| Relative activity
|
| WT (ALDH2*1)
|
|
|
|
|
|
| ALDH2*2
| E504K[6]
| 504
| Glu → Lys
| East Asian
| 26.6%
| 0%
|
| ALDH2*3
| I41V
| single-carbon change in the AA side chain [2]
| African
| 0.6%
| 60%
|
| ALDH2*4
| P92T[7]
| 92
| Pro → Thr
| Latino
| 2.5%
| 32%
|
| ALDH2*5
| T244M[8]
| 244
| Thr → Met
| South Asian
| 0.7%
| 38%
|
| ALDH2*6
| V304M[9]
| 304
| Val → Met
| Latino
| 2.4%
| 11%
|
| ALDH2*7
| R338W[10]
| 338
| Arg → Trp
| Finnish
| 1.2%
| 23%
|
