The oncogene Bcl2 encodes a membrane protein that blocks a step in a pathway leading to apoptosis or programmed cell death. Studies in human and mouse suggest that the protein encoded by this gene (referred to as Bcl2-associated athanogene) binds to Bcl2 protein. It enhances the anti-apoptotic effects of Bcl2 and represents a link between growth factor receptors and anti-apoptotic mechanisms. At least two protein isoforms are encoded by this mRNA through the use of a non-AUG (CUG) start site and an alternative, downstream, AUG translation initiation site. [provided by RefSeq, Jul 2008]