Up until this age, the baby will appear to be developing normally. When Tay-Sachs begins to show itself, the baby will stop interacting with other people, and develop a staring gaze. Normal levels of noise will startle the baby to an abnormal degree. By about a year of age, the baby will have very weak, floppy muscles, and may be completely blind. The head will be quite large.
Seizures become a problem between ages one and two , and the baby usually dies by about age four.
Juvenile hexosaminidase A deficiency. Symptoms may begin around age five, or may not occur until age 20-30. The disease is milder. Speech becomes slurred. The individual may have difficulty walking due to weakness, muscle cramps, and decreased coordination of movements.