Tay-Sachs Disease [HEXA]: A progressive neurodegenerative disorder which is characterized by the onset in infancy of developmental retardation, followed by paralysis, dementia and blindness, with death in the second or third year of life. A gray-white area around the retinal fovea centralis, due to lipid-laden ganglion cells, leaving a central ‘cherryred’ spot is a typical funduscopic finding. Pathologic verification is provided by the finding of the typically ballooned neurons in the central nervous system. An early and persistent extension response to sound (‘startle reaction’) is useful for recognizing the disorder.
Ashkenazi Jewish Carrier Frequency: 1 in 27
Sephardic-Mizrahi Jewish Carrier Frequency: 1 in 125
Tay-Sachs enzyme analysis using blood must be done in addition to DNA for complete screening.