Monday, December 22, 2014
Testing for Huntington's Disease
I just found out that my husbands mother died from Huntington`s disease. My husband is one of 6 sons and had no contact with his brothers after his mother died. He told me (and thought) that his mother had Parkinson`s. We married when my husband was 45 and have two children, 14 & 15 years old. My husband is 62 now. My daughter wanted to know if any of her uncles were still alive so I looked up a brother in Georgia and found out the following: The oldest brother died from diabetes. The second died from Huntingtons and started showing signs in his 40`s. Brother`s 3 & 4 both had Huntingtons and died in their late 60`s early 70`s. The youngest bother (my husband is #5) committed suicide in his 30`s. Half of the nephews and nieces have Huntington`s. I asked my husband to get tested for the sake of our children. He feels that at age 62 he would have shown signs of it by now. I`ve read that if he doesn`t have it our children won`t. My question is: Could my husband have it but never show signs thus passing to our children? My husband feels that since 3 possibly 4 out of the 6 boths had the disease, plus he`s already 60, his odds are great. I`m just afraid for my children. Please help.
The question of when and whether to get genetic testing for Huntington's disease (HD) is a very personal issue, and the decision to get tested may depend upon many factors. The best way to explore these issues and learn more details about Huntington's disease may be to meet with a genetics counselor who has experience with Huntington's disease.
However, I will try to answer some of the questions you have asked.
You asked whether you husband might never show signs of the disease but still pass the disease on to your children. If your husband in fact caries the HD gene, it is unlikely that he would never show any signs of the disorder during his lifetime.
However, the age of onset of symptoms of the disease can vary quite a bit. This may be dependent upon the exact nature of the individual's HD gene, but may also be affected by other genes he carries and environmental factors.
Onset of symptoms after age 60 is uncommon but not unheard of. Symptom onset is usually very gradual and may include changes in behavior (depression, mood swings, poor impulse control, obsessive compulsive behaviors etc) gradual impairment of cognitive function and motor changes including involuntary movements (chorea) trouble with walking or balance, and difficulty swallowing.
You have expressed concern about your children. If you husband carries the gene defect that causes HD, your children would each individually have a 50/50 chance of getting the disease. However, if your husband has HD, he would be more likely to have a late onset variant, as he currently does not show symptoms. That would make it more likely that your children would have a later onset variant. One would then most commonly not expect to see symptoms in your children for at least 20-40 years.
We have made a lot of progress in research in Huntington's disease in the last five years and currently are studying several agents that seem to slow the rate of disease progression. There is some exciting work in animal models of HD suggesting that we may eventually be able to prevent disease onset or cure the disorder in the upcoming years. We are hoping that carrying the HD gene will not be a significant medical issue for future generations.
Feel free to call our HDSA Center social worker Barbara Heiman (614) 292-9960 or our Genetics counselor Allison Seward (614)688-8672 if you have other concerns that you would like to discuss or if you and your husband would like to get genetics counseling.
Sandra K Kostyk, MD, PhD
Assistant Professor of Neuroscience
Clinical Assistant Professor of Neurology
College of Medicine
The Ohio State University