This family represents the N-terminal region of the mammalian BAALC proteins. BAALC (brain and acute leukaemia, cytoplasmic), that is highly conserved among mammals but evidently absent from lower organisms. Two isoforms are specifically expressed in neuroectoderm-derived tissues, but not in tumors or cancer cell lines of non-neural tissue origin. It has been shown that blasts from a subset of patients with acute leukaemia greatly overexpress eight different BAALC transcripts, resulting in five protein isoforms. Among patients with acute myeloid leukaemia, those overexpressing BAALC show distinctly poor prognosis, pointing to a key role of the BAALC products in leukaemia. It has been suggested that BAALC is a gene implicated in both neuroectodermal and hematopoietic cell functions.