The protein encoded by this gene is a member of the ATP-binding cassette (ABC) transporter superfamily. ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White). The encoded protein is a member of the White subfamily and plays an important role in cellular cholesterol homeostasis. This protein functions as either a homodimer or as a heterodimer with another ABC subfamily protein such as ABCG1. [provided by RefSeq, Jan 2017].