What it is
Tay-Sachs disease is an inherited condition caused by changes in the HEXA gene. That gene normally helps the body break down a fatty substance called GM2 ganglioside, so when it does not work the substance builds up and damages nerve cells.
Signs and symptoms
Blindness
Loss of vision develops as the disease advances, alongside seizures and increasing stiffness of the limbs.
GM2-ganglioside accumulation
Because the HEXA enzyme cannot break it down, GM2 ganglioside builds up inside nerve cells, which drives the damage seen in the disease.
Exaggerated startle response
An exaggerated startle response to sound, together with overactive reflexes, is a common early sign as the condition affects the nervous system.
Seizure
Seizures develop as the condition progresses and the nervous system is increasingly affected.
Psychomotor deterioration
From around 3 to 6 months of age a baby with Tay-Sachs gradually loses motor skills and alertness they had gained, a steady decline over time.
Autosomal recessive inheritance
Tay-Sachs is passed on in an autosomal recessive pattern: a child develops it only when they inherit a changed copy of the gene from both parents.
Cherry red spot of the macula
A 'cherry-red spot' at the centre of the retina is a characteristic eye finding in Tay-Sachs and can be seen by a doctor looking into the eye.
Treatment and management
No disease-modifying treatment is established for this condition in the research mapped here. This is a stated, reviewed fact, not a missing piece of this guide.
That does not mean nothing can be done. Supportive and symptomatic care, managing specific symptoms and complications as they arise, can still matter a great deal. What is right for any individual is a conversation for their own care team.
Turn this into questions for your doctor
The hardest part is often knowing what to ask. PatientLead Health helps families turn what is on this page into the right questions for their care team.
How to read the evidence labels
Where this comes from
This guide is built from 1 published source(s). Every claim above links back to one of them. Click any source ID to read the original on PubMed.