Tay Sachs disease is a rare genetic disorder caused by mutations in the HEXA gene resulting in a buildup of fatty substances in the brain and nerves. It typically causes severe mental and physical deterioration in children from a young age and is fatal by age 5. It is an autosomal recessive disorder requiring one defective copy of the gene from each parent, who are often carriers themselves. There is currently no cure for Tay Sachs disease.

1. Tay Sachs Disease
By: Alex Mancino

2. Background info on Tay Sachs
• Causes intense mental and physical
deterioration at a young age
• Currently there is no cure
• Mutations in the HEXA gene cause
Tay-Sachs disease

3. Genetic Information
• Autosomal recessive genetic disorder
• It is caused by a genetic defect in a single gene
with one defective copy of that gene inherited
from each parent
• Mutation is on 15th chromosome

4. Mutation on 15th chromosome

5. When each parent has the gene…
• 50% chance that their child will be a carrier,
but not have the disease
• 25% chance that their child will not be a
carrier and not have the disease
• 25% chance that their child will have the
disease

6. What actually happens?
• Harmful quantities of a fatty substance called
ganglioside GM2 build up in tissues and nerve
cells in the brain
• Insufficient activity of an enzyme called beta-
hexosaminidase A that catalyzes the
biodegradation of the gangliosides

7. Affected Body Parts
• Red spot behind eye, forms
– Blindness follows
• Hearing loss
• Complete loss of physical movement
– Seizures

8. Diagnosis
• Complete physical evaluation
• A detailed history of symptoms and family
hereditary disorders
• Eye examination
– Looking for red spot on eye
• Blood test
– A blood test can measure hexosaminidase A (hex A)
activity
– Parents can get blood tests to see if they carry the Tay
Sachs gene

9. Prognosis
• You’re screwed
• Death usually occurs by the time the child is 5
years old
• In cases where kids get Tay Sachs later on in
childhood (rare) they usually die once the
reach their teen years

10. History of Disease
• Named after Warren Tay and Bernard Sachs
• Warren Tay
– First described red spot on retina in 1881
• Bernard Sachs
– Did further research and described the changes in
cells during Tay Sachs
– also noted an increased prevalence of Tay Sachs
disease in the eastern and central European
Jewish population

11. Bibliography
• http://nervous-system.emedtv.com/tay-sachs-
disease/history-of-tay-sachs-disease.html
• http://www.ninds.nih.gov/disorders/taysachs/taysachs.htm
• http://ghr.nlm.nih.gov/condition/tay-sachs-disease
• http://kidshealth.org/parent/medical/genetic/tay_sachs.htm