<Tr> <Td_colspan="2"> (edit on Wikidata) </Td> </Tr> <P> Tay--Sachs disease is a genetic disorder that results in the destruction of nerve cells in the brain and spinal cord . The most common type, known as infantile Tay--Sachs disease, becomes apparent around three to six months of age with the baby losing the ability to turn over, sit, or crawl . This is then followed by seizures, hearing loss, and inability to move . Death usually occurs in early childhood . Less commonly the disease may occur in later childhood or adulthood . These forms are generally milder in nature . </P> <P> Tay--Sachs disease is caused by a genetic mutation in the HEXA genes on chromosome 15 . It is inherited from a person's parents in an autosomal recessive manner . The mutation results in problems with an enzyme called beta - hexosamidase A which results in the buildup of the molecule GM2 ganglioside within cells, leading to toxicity . Diagnosis is by measuring the blood hexosaminidase A level or genetic testing . It is a type of sphingolipidoses . </P> <P> The treatment of Tay--Sachs disease is supportive in nature . This may involve multiple specialities as well as psychosocial support for the family . The disease is rare in the general population . In Ashkenazi Jews, French Canadians of southeastern Quebec, and Cajuns of southern Louisiana, the condition is more common . Approximately 1 in 3,600 Ashkenazi Jews at birth are affected . </P>

What type of protein is affected in cells of individuals with tay-sachs