Gene HEXA
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Also known as
TSD, hexosaminidase A alpha subunit, Tay-Sachs enzymeOverview
HEXA (Hexosaminidase Subunit Alpha) encodes the alpha subunit of beta-hexosaminidase A, a lysosomal enzyme that degrades GM2 ganglioside in nerve cells. The functional enzyme consists of alpha and beta subunits and requires the GM2 activator protein for activity. Beta-hexosaminidase A is essential for breaking down lipids in the brain and nervous system.Mutations in HEXA cause Tay-Sachs disease, a severe neurodegenerative disorder characterized by progressive destruction of nerve cells. The infantile form presents with developmental regression, seizures, and death by age 4-5. Late-onset forms can present with motor neuron disease-like symptoms. Tay-Sachs is more common in Ashkenazi Jewish, French-Canadian, and Cajun populations.
Understanding your HEXA genetic status is important for carrier screening, particularly for individuals of high-risk ethnic backgrounds. Carrier testing and genetic counseling are recommended for at-risk populations to inform family planning decisions.