Zebra finch ALDH3A3 encodes a full-length peptide that shares 84.1 per cent similarity with the ALDH3A2 parent gene. Zebrafish has three aldh3a2 duplications, which include two full-length genes (aldh3a2.2 and aldh3a2.3) and a significantly truncated partial duplication (aldh3a2p1). The degree of sequence identity that Aldh3a2.2 and Aldh3a2.3 share with the parent peptide (64.9 per cent and 70.9 per cent, respectively) suggests that they diverged sufficiently long ago to be considered new ALDH3A family members. They also share 64.9 per cent identity with each other and less than 60 per cent identity with zebra finch ALDH3A3, suggesting that all three genes are paralogues rather than orthologues. Zebra finch ALDH3A5 should also be considered a new functional ALDH family member. In addition, the zebrafish pseudogene aldh3a2p1, if translated, would share the highest degree of sequence identity with aldh3a2.3. Thus, the pseudogene most likely reflects a more recent partial duplication of this gene.
