(7: How is it diagnosed)
Tests:
- hereditary family disorder check
- diagnostic blood test, which checks the levels of hexosaminidase (an enzyme); hexosaminidase levels are low or absent in those with Tay-Sachs disease
- eye examination, which checks for a cherry-red spot in the back of a patient's eyes, which is a symptom of Tay-Sachs

(8: History)
- Tay-Sachs is named after Warren Tay (1843-1927), a British ophthalmologist who in 1881 described a patient with a cherry-red spot on the retina of the eye, and Bernard Sachs (1858-1944), a New York neurologist whose work several years later provided the first description of the cellular changes in Tay-Sachs disease
- in August 1969, Dr. Shintaro Okada and Dr. John S. O'Brien published the discovery of the Hexosaminidase A deficiency in Tay-Sachs
- the gene that causes Tay-Sachs was identified in the late 1980s and by the mid-1990s, and over 75 different mutations had been identified
- currently there are over 100 mutations reported from all ethnic groups