This gene encodes a protein that binds to heterotrimeric G proteins and is targeted to melanosomes in pigment cells. This protein is thought to be involved in intracellular signal transduction mechanisms. Mutations in this gene cause ocular albinism type 1, also referred to as Nettleship-Falls type ocular albinism, a severe visual disorder. A related pseudogene has been identified on chromosome Y. [provided by RefSeq, Dec 2009]