My mom had JHD, I'm 16 and don't have symptoms, could I still have it?
HDYO has more information about HD available for young people, parents and professionals on our site:
Q. If my mom had Juvenile Huntington’s Disease, and I am now 16 and have not had any symptoms of Juvenile Huntington’s Disease, does that mean I do not carry the disease at all or can I still develop the disease at the older age?
Victor, Teen, USA
A. Dear Victor,
Thanks for the question, which is a really tricky one. The reason it is tricky is that people with Juvenile HD don’t have children very often so there’s not much real life data to go on.
CAG repeat numbers are inherited fairly stably from female parents. What that means is that, if you inherited the HD gene from your mum, it would probably be of a similar length to hers. This means that, if you had HD, it’s very likely to be of the Juvenile Onset variety.
However, I think that 16 is still a bit young to say you don’t carry the disease. Seeing as you have reached 16 unaffected, the risk of you carrying the HD gene is below 50% but it is still not 0%. I think that if you reached your late 20’s with no symptoms, then your risk of carrying the gene would be pretty low.
In the end, the best way of quantifying risk, if that is what you want to do, is to take the genetic test. In most countries, predictive tests are not normally performed on people under 18 and there are other things to take into consideration, (such as the availability of life insurance and health insurance) which can be discussed with a genetic counsellor.