Beta-hexosaminidase subunit beta is an enzyme that in humans is encoded by the HEXB gene.1NOU, 1NOW, 1NP0, 1O7A, 2GJX, 2GK1, 3LMY, 5BRO307415212ENSG00000049860ENSMUSG00000021665P07686P20060NM_001292004NM_000521NM_010422NP_000512NP_001278933NP_034552The HEXB gene lies on the chromosome location of 5q13.3 and consists of 15 exons, spanning 35-40Kb.HEXB is one of the two subunits forming β-hexosaminidase which functions as a glycosyl hydrolase that remove β-linked nonreducing-terminal GalNAc or GlcNAc residues in the lysosome. Inability of HEXB will lead toβ-hexosaminidase defect and result in a group of recessive disorders called GM2 gangliosidoses, characterized by the accumulation of GM2 ganglioside.Genetic defects in HEXB can result in the accumulation of GM2 ganglioside in neural tissues and two of three lysosomal storage diseases collectively known as GM2 gangliosidosis, of which Sandhoff disease (defects in the β subunit) is the best studied one. Patients present with neurosomatic manifestations. Therapeutic effects of Hex subunit gene transduction have been examined on Sandhoff disease model mice. Intracerebroventricular administration of the modified β-hexosaminidase B to Sandhoff mode mice restored the β-hexosaminidase activity in the brains, and reduced the GM2 ganglioside storage in the parenchyma.HEXB has been found to interact with HEXA and ganglioside.