MAX（MYC associated factor X），癌症关联基因，基因ID：4149，该基因编码的蛋白质是碱性螺旋环螺旋亮氨酸拉链（bhlhz）转录因子家族的成员。它能与其他家族成员形成同二聚体和异二聚体，包括mad、mxi1和myc。myc是一种参与细胞增殖、分化和凋亡的肿瘤蛋白。同二聚体和异二聚体竞争一个共同的dna靶位点（e盒），这些二聚体形式之间的重排提供了一个复杂的转录调控系统。据报道，该基因突变与遗传性嗜铬细胞瘤有关。这个基因的一个假基因位于第7号染色体的长臂上。选择性剪接导致多个转录变体。[由RefSeq提供，2012年8月]The protein encoded by this gene is a member of the basic helix-loop-helix leucine zipper (bHLHZ) family of transcription factors. It is able to form homodimers and heterodimers with other family members， which include Mad， Mxi1 and Myc. Myc is an oncoprotein implicated in cell proliferation， differentiation and apoptosis. The homodimers and heterodimers compete for a common DNA target site (the E box) and rearrangement among these dimer forms provides a complex system of transcriptional regulation. Mutations of this gene have been reported to be associated with hereditary pheochromocytoma. A pseudogene of this gene is located on the long arm of chromosome 7. Alter。