Alzheimer’s disease - early onset

Professor Kenneth Kosik discusses early-onset Alzheimer's disease, which affects 1% of all people with the disease.

Alzheimer’s disease is not a monolithic entity. It comes in some different varieties, and perhaps one way to divvy up the clinical realm is looking at the age of onset. There is a group of people who have an early age of onset. Those people often have Alzheimer’s disease running in their families and, as we’ve learned more and more about that group, we’ve come to realize that they do indeed represent a very special category. Many of the people with early-onset Alzheimer’s, who have a family history, will also carry a gene mutation; a mutation that leads to Alzheimer’s disease in 50% of the offspring of the person who already has it. About 1% of all people with Alzheimer’s disease have this form, and for those who carry that particular kind of mutation, the likelihood of getting it approaches 100% - in contrast to some other types of mutations that we know about, where your risk increases but you don’t have this very inevitable possibility of developing the disease.