Hexosaminidase A

Tay-Sachs is caused by a mutation in the HEXA gene on chromosome 15. The HEXA gene codes for the alpha subunit of the hexosaminidase A enzyme which is necessary for breaking down GM2 gangliosides in nerve cells. When there is a mutation in the coding for alpha subunit of the hexosaminidase A it does not function properly and leads to an accumulation of GM2 which is toxic and eventually causes cell death. Sandhoff is characterized by loss of function of both the alpha and beta subunit of hexosaminidase A enzyme. For more information visit: http://ghr.nlm.nih.gov/gene=hexa