ALDH2 Expression, Alcohol Intake and Semen Parameters among East Asian Men.

Purpose: Inactivating mutations in mitochondrial aldehyde dehydrogenase 2 (ALDH2) are highly prevalent. The most common variant allele, , is present in 40%-50% of East Asians, and causes acetaldehyde accumulation, flushing and tachycardia after alcohol intake. The relationship between alcohol intake and ALDH2 genotype on semen parameters remains unknown.

Materials And Methods: We conducted a cross-sectional study to determine the association between ALDH2 genotype, alcohol consumption and semen parameters among East Asian men. Volunteers completed a survey and submitted a semen sample for analysis. Participants were genotyped to determine ALDH2 status (, , ), and immunohistochemical staining was used to determine protein expression of ALDH2 in spermatozoa.

Results: Of 112 men 45 (40.2%) were carriers. Among carriers, alcohol consumption was associated with significantly lower total sperm motility (median 20% [interquartile range 11%-42%] vs 43% [IQR 31%-57%], p=0.005) and progressive sperm motility (19% [IQR 11%-37%] vs 36% [IQR 25%-53%], p=0.008). Among alcohol consumers, carriers had significantly lower total sperm motility (20% [IQR 11%--42%] vs 41% [IQR 19%-57%], p=0.02), progressive sperm motility (19% [IQR 11%-37%] vs 37% [IQR 17%-50%], p=0.02) and total motile sperm count (28 million [M; IQR 9-79M] vs 71M [IQR 23-150M], p=0.05) compared to individuals. Secondly, ALDH2 expression in human spermatozoa was significantly lower in carriers ( vs , p=0.01; vs , p <0.001).

Conclusions: Our findings suggest genotyping ALDH2, coupled with alcohol cessation counseling, may improve semen parameters among men.