This gene encodes a member of the immunoglobulin superfamily. The gene is located in a cluster of butyrophilin-like genes in the juxta-telomeric region of the major histocompatibility complex on chromosome 6. A pseudogene of this gene has been identified in this cluster. The encoded protein is an integral plasma membrane protein involved in lipid, fatty-acid, and sterol metabolism. Alterations in this gene may be associated with several disease states including metabolic syndrome. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene.