When there is a suspicion that a person might have Tay–Sachs disease, regardless of the age of onset, the initial testing starts with an enzyme assay to determine the activity of hexosaminidase in leukocytes, fibroblasts, or serum. In individuals with Tay-Sachs disease, hexosaminidase enzyme activity is decreased.
After decreased hexosaminidase enzyme activity in an individual is confirmed, there’s a possibility to pursue confirmation by molecular analysis as well.
Patients with infantile onset of the disease have a “cherry red” spot in the retina, easily detectable by a doctor using an ophthalmoscope. This spot is due to gangliosides in the retinal ganglion cells. This red spot is the only normal part of the retina, and it shows up because of the contrast to the rest of the retina.
Tay-Sachs disease cannot be cured, but there are a few ways to prevent or reduce it. Prenatal diagnosis is a way to determine if partners are both identified as carriers. If they are, prenatal genetic testing can determine if the fetus has inherited the defective gene from the parents.
It is possible to detect the defective gene through the preimplantation genetic diagnosis. Mother’s eggs are tested in vitro for the Tay-Sachs disorder. This allows only the healthy embryos to be transferred into the womb.