What is Huntington’s Disease?
Huntington’s disease is a progressive, inherited neurological disorder caused by a mutation (CAG repeat expansion) in the HTT gene. This mutation leads to the production of an abnormal form of the huntingtin protein, which gradually damages nerve cells in the brain. The condition follows an autosomal dominant inheritance pattern — meaning only one copy of the defective gene is enough to cause the disease. Symptoms typically appear in adulthood, but juvenile forms can occur.
Key Features
- Progressive degeneration of nerve cells in the brain
- Affects movement control, cognitive functions, and emotional stability
- Symptoms usually begin between ages 30 and 50
- Worsens over 10–25 years after onset
Common Symptoms
- Involuntary movements (chorea) or muscle rigidity
- Difficulty with coordination and balance
- Cognitive decline and memory loss
- Speech and swallowing difficulties
- Mood disorders such as depression, irritability, and anxiety
- In later stages, severe physical and mental disability
How to Reduce the Risk
- Carrier and predictive genetic testing to identify the HTT gene mutation before symptoms appear
- Preimplantation Genetic Testing for Monogenic Disorders (PGT-M) during IVF to select embryos without the mutation
- Prenatal genetic testing for early detection during pregnancy
- Genetic counseling for individuals with a family history of Huntington’s disease