ABCG4 is a symbol for the gene, ATP binding cassette subfamily G member 4, in humans. Other names include: ATP-binding cassette sub-family G member 4; putative ABC transporter; ATP-binding cassette, subfamily G, member 4; ATP-binding cassette, sub-family G (WHITE), member 4; WHITE2. The encoded protein has an amino acid length of 646 and a mass of 71.9 kDa. Other isoforms may exist. ABCG4 is a member of the ABC transporter superfamily, ABCG family, Eye pigment precursor importer (TC 3.A.1.204) subfamily. This gene shares homology with other species, including: Mouse, Chicken.