Much has been done in the past four decades to better understand, improve diagnostic measures of, and prevent hexosaminidase deficiency diseases, yet all of them - Tay-Sachs, Sandhoff, and Late Onset Tay-Sachs (LOTS) - remain diseases without treatment. Much work remains to be done to understand and effectively treat these diseases. To date, no comprehensive assessment of the natural history of Tay-Sachs or Sandhoff has been undertaken. The information that is gathered through this study will characterize and describe the Tay-Sachs disease population as a whole, including the variability and progression of this disease. This information, in turn, will function as a point of reference against which to assess the efficacy of therapeutic interventions. Therapeutic interventions may include any treatments/therapies the subject may have undergone in the past, including hematopoietic cell transplantation, and/or the administration of miglustat, acetylcysteine, or other pharmaceutical agents; and possible future gene therapies.
Inclusion Criteria: Any person who has been diagnosed with a hexosaminidase deficiency disease can be included in this study. Exclusion Criteria: The only exclusion criteria is a desire not to participate in this study.