The protein encoded by this gene is a member of the family of soluble N-ethylmaleimide-sensitive fusion protein-attachment protein receptors (SNAREs) that function in intracellular trafficking. This family member is involved in vesicular transport between endosomes and the trans-Golgi network. It is a vesicle-associated SNARE (v-SNARE) that interacts with target membrane SNAREs (t-SNAREs). Polymorphisms in this gene have been associated with binocular function, and also with susceptibility to colorectal and lung cancers. A recurrent rearrangement has been found between this gene and the transcription factor 7-like 2 (TCF7L2) gene in colorectal cancers. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2015]