Abh, or AlkB homolog 1, histone H2A dioxygenase, is a human gene encoded by ALKBH1. It may also be known as: DNA oxidative demethylase ALKBH1; Alkylated DNA repair protein alkB homolog 1; Alpha-ketoglutarate-dependent dioxygenase ABH1; DNA lyase ABH1; DNA oxidative demethylase ALKBH1 ; ABH; ABH1; ALKBH; alkB; alkB, alkylation repair homolog 1 (E. coli); hABH. The encoded protein is an enzyme with an amino acid length of 389 and a mass of 43.8 kDa. Abh is a member of the AlkB family. Homologs of this gene exist in other organisms, including: Arabidopsis, Frog.