a rare hereditary metabolic disorder involving an enzyme deficiency that causes a build-up of lipids (fatty substances; see lipid) in brain and nerve tissue, resulting in mental retardation, paralysis, epileptic seizures, blindness, and, ultimately, death. Tay-Sachs disease mostly affects very young children, esp of eastern European Jewish descent
[named after Warren Tay d.1927, British physician, and Bernard Sachs d.1944, American neurologist, who each independently described it]