Understanding Huntington's Disease

Understanding Huntington's Disease

Huntington's disease is an inherited neurodegenerative disorder. It is passed on to children from one or both parents (though two parents with Huntington's is extraordinarily rare) in an autosomal dominant manner. This is different from autosomal recessive disorder, which requires two altered genes (one from each parent) to inherit the disorder.

So if one parent has it, and passes the gene on to a child, that child will develop Huntington's disease if they live long enough and each of that child's' children will have a 50% chance of inheriting the gene, and so on and so forth. If you do not have the HD gene you can't pass it on to your children and if your mate doesn't have it then there is no way your child will develop the disease (spontaneous cases of HD are less than 0.1%). There are no "carriers" for Huntington's. HD is present in all areas of the world but is dominant in western Europeans and their descendants. In the United States every 1 in 10,000 people have developed HD, that's 300,000 people with another 150,000 at risk (all of those with children have a 50% chance of passing it on).

The HD gene is present at birth, but doesn't usually develop until a persons thirties or forties. Though this is the most common time for symptoms to develop, there have been cases were symptoms developed as young as 2 and as old as 80. Symptoms begin gradually and increase over time.

Huntington's disease affects three main areas of function: motor (physical), mood (emotional), and cognition (psychological). Motor function disturbances can fall into too much movement and too little movement. Chorea, involuntary dance-like movements, can affect any part of the body. It looks like restlessness, wrigg...

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...l Center: Huntington Disease Clinic web page.

Updated 10-1-01.

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