Correlation between alcohol-induced asthma and acetaldehyde dehydrogenase-2 genotype.
BACKGROUND
Alcohol-induced asthma, a phenomenon characteristic of Asians, is due to differences in alcohol metabolism, particularly acetaldehyde metabolism. We investigated the effect of polymorphism in acetylaldehyde dehydrogenase 2 (ALDH2) gene on the response to alcohol challenge testing in a group of Japanese asthmatic subjects and normal subjects.


METHODS
Subjects were 32 asthmatic subjects and 30 healthy individuals. We measured the change in FEV1 after ingestion of 30 gm of ethanol. Blood ethanol, acetylaldehyde, and histamine concentrations were determined. ALDH2 gene type was established by polymerase chain reaction.


RESULTS
Ethanol provocation test results were positive in 15 (47% responders) asthmatic subjects. The blood ethanol concentration was similar in responders and nonresponders. The fall in FEV1 was associated with a rise in blood acetaldehyde and histamine concentrations. The response to oral ethanol challenge was positive in three (19%) of 16 patients with normal homozygote ALDH2 genotype, 10 (71%) of 14 patients with type mutant heterozygote, and two (100%) of two patients with type mutant homozygote ALDH2 genotype.


CONCLUSIONS
Alcohol-induced asthma is probably caused by increased blood acetaldehyde concentration resulting from abnormalities of ALDH2 enzyme activity based on ALDH2 genotype differences.
Takao
A
A
Second Department of Internal Medicine, Nagasaki University School of Medicine, Japan.
Shimoda
T
T
Kohno
S
S
Asai
S
S
Harda
S
S
D000079:Acetaldehyde / Q000097:blood; D000328:Adult; D000368:Aged; D000445:Aldehyde Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D000485:Allergens / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood; D001249:Asthma / Q000097:blood / Q000139:chemically induced / Q000201:enzymology*; D000431:Ethanol / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood; D005260:Female; D005838:Genotype; D006632:Histamine / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D013147:Spirometry
D000485:Allergens; D000431:Ethanol; D006632:Histamine; D000445:Aldehyde Oxidoreductases; C018699:aldehyde dehydrogenase (NAD(P)+); D000079:Acetaldehyde