Polymorphism of a class 3 aldehyde dehydrogenase present in human saliva and in hair roots.

The types of aldehyde dehydrogenases (ALDH) present in human hair roots and in saliva were investigated. ALDH was detected by activity staining following separation of crude extracts by isoelectric focusing. Hair roots were found to express ALDH1, ALDH2, ALDH3, and ALDH4, whereas saliva expressed ALDH3. Two different patterns of ALDH3 were detected in hair roots collected from 42 donors, 40 expressed one pattern (variant I) and two another pattern (variant II) of activity staining. The variant I pattern of hair root ALDH3 changed with repetitive freezing and thawing of the sample, whereas the variant II pattern was stable. In contrast to hair root ALDH3, all patterns of ALDH3 activity in saliva were stable. The patterns of ALDH3 activity present in human hair roots that had been frozen and thawed twice matched those present in saliva collected from the same individual. Three polymorphisms of ALDH3 (variants I, II, and III) were detected in the 33 saliva samples analyzed. Variants I and II were inherited in each of three generations of a 10-member family.