Saturday, November 22, 2014
Risk of Genetic Predisposition to Alzheimer's
Hello: Your website is very helpful and informative.
My question: My father is currently in hospice. He has Alzheimer`s disease and is dying. My father`s brother also has Alzheimer`s (earlier stage). I asked my sister who is a physician, and is older than myself, if my grandfather (on my father`s side) had Alzheimer`s. She said Yes. She said, because my mother does not have it, she thinks it is only males in my family that can inherit it. Here`s the question: Is that true? And if it is true, what does it mean for my 3 nephews (from my other sister). Are they possibly doomed to get it?
Your answer will be appreciated.
Hello. I'm glad you found the website to be helpful. I'm sorry to hear, though, about your father's condition. Given the history of Alzheimer disease in your relatives, I can understand your interest in learning more about risk for Alzheimer's disease.
Although it appears to be the case in your family (at this point in time) that only males have had Alzheimer's disease, it does affect both males and females. As far as we know, there are no genes that cause only males to be affected with Alzheimer's disease.
We all have a general population risk of developing Alzheimer's disease, which is about 10%-15% over our lifetimes. It is true that having a family history of the disease raises a person's risk of developing Alzheimer disease, although it is difficult to say by how much.
You did not mention how old your father or your uncle or grandfather were when they first developed Alzheimer disease. If the average of onset in your family is less than 60 years, it might be worthwhile to consult a geneticist or genetic counselor to discuss the possibility of early onset familial Alzheimer's disease, which can be caused by a change in a single gene. In families where this occurs, both males and females are at equal risk of inheriting the changed gene and developing Alzheimer's.
Melissa Butson, ScM, CGC
Formerly, Clinical Adjunct Instructor of Neurology
School of Medicine
Case Western Reserve University