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Symptoms take a long time for some people

March 8, 2014

Huntington's Disease Youth Organization

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Symptoms take a long time for some people

Q. I would like to know why for some HD patients it takes so long for the symptoms to appear. If the gene mutation is there since the beginning, why only when those patients get to their 40’s, symptoms start to be visible?

Victor, 19, Brazil

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A. Dear Victor,

Thanks for your question. It’s not easy to answer!

The HD gene makes a protein which damages cells in the body. You are right that this process happens from the beginning but human cells are very good at dealing with the protein for years. Also, the human body has lots of “back-up systems” (especially the brain) so, when one part is not working so well, other parts take over some of the work.

I think that, in future, research will be focussed on the processes that are involved with dealing with the HD protein. I think these processes will be controlled by a few other genes (not the HD gene). If we could boost those functions, we’d stand a good chance of delaying the start of the disease.

Best wishes

Hugh Rickards