Evidence of betaA2-crystallin expression has been detected in human lenses. The protein, which co-elutes with betaA1/A3 from reversed phase HPLC separation of beta(L)-crystallins, accounts for 1-2% of the lens crystallins. Its molecular mass, M(r) 22 006, is consistent with the cDNA deduced sequence with addition of acetylation at the N-terminal serine residue. Approximately 20% of the protein is phosphorylated at Ser30.