How is Huntington's disease (HD) diagnosed?
A neurologist (a doctor specializing in the brain and nerves) will perform a physical exam. They will look for twitches and jerking as well as problems with your balance, reflexes and coordination. Your neurologist will also want to know if anyone else in your family has the disease.
You will have tests to rule out other conditions that cause similar symptoms and to confirm an HD diagnosis. Tests include:
- Blood test.
- Genetic testing.
- Imaging tests such as magnetic resonance imaging (MRI) and computed tomography (CT) scan.
What is genetic testing like?
Your healthcare provider draws your blood and sends it off to a laboratory to look at your DNA. The test determines if you have a mutation on the HTT gene. A genetic counselor (someone who specializes in genetic testing) will discuss the process and results with you.
Occasionally, genetic testing doesn’t provide a clear answer. Your HTT gene may be somewhere in the middle — creating longer-than-normal proteins but not providing a definite answer. In that case, imaging tests may help. They can show whether your brain has had any HD-related changes. Your provider may also ask if your family members can come in for genetic testing, too.
Can you find out if you have Huntington’s disease (HD) before symptoms appear?
If one of your parents or siblings has HD, your risk of having it is high. Predictive genetic testing — testing for genetic diseases before symptoms start — can tell if you have the gene mutation.
People have different responses to learning about a disease they’ll get someday. Knowing about the gene could help you make family plans and financial decisions. But it could also be emotionally difficult, especially since you can’t prevent the disease. It is essential to discuss testing with your genetic counselor to see whether finding out is the best decision for you.