This gene encodes a protein with limited similarity to L-amino acid oxidase which contains the conserved amino acids thought to be involved in catalysis and binding of flavin adenine dinucleotide (FAD) cofactor. The expression of this gene can be induced by interleukin 4 in B cells, however, expression of transcripts containing the first two exons of the upstream gene is found in other cell types. Multiple transcript variants encoding different isoforms have been found for this gene.