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What is HD

What is HD

Huntington’s disease (HD) is a neurodegenerative illness that causes damage to the brain that results in changes in movement, thinking and behavior. HD is caused by abnormal genes that are present at birth. However, the symptoms don’t start to appear until a person is around 35-50 years old. Once the symptoms start, they will become worse over a 10 to 20 year period before a person sadly passes away. 

Much is known about the defective gene that causes HD, but a cure has not been developed yet. Many researchers around the world are working to find ways to slow down the disease or stop the symptoms from starting. In the meantime, there are medical treatments and evidence-based strategies to treat the physical and mental symptoms. 

HD is an inheritable disease. If a parent has HD, each of their children has a 50/50 chance of having the abnormal gene and developing the symptoms of HD.  

An abnormal HD gene is much longer than usual because of CAG repeats. If the CAG sequence is repeated 40 or more times, a person will develop the symptoms of HD. If they have somewhere between 27-39 CAG repeats, they have a smaller risk of getting the symptoms and passing the disease on to children. If a person has fewer than 27 CAG repeats, they won’t have HD or pass it on. Learn more about genetic testing.