New Gene Variations Linked to Alzheimer's Disease Risk

What causes Alzheimer's disease? If only it was just one thing -- then scientists could develop a "silver bullet" and make it go away. Unfortunately, it's not that simple.

Most scientists agree that a combination of genetic and environmental factors determine whether or not someone will develop Alzheimer's. Genetically speaking, the APOE-e4 gene is the most well-known gene variation that seems to increase the risk of developing the late-onset (after age 65) form of the disease.

However, a recent study by Rudi Tanzi, Ph.D., Director of the Genetics and Aging Unit at Massachusetts General Hospital, and his colleagues suggests that several additional gene variations may be linked to late-onset Alzheimer's. The study was published in the November 7th issue of the American Journal of Human Genetics.

Tanzi and his team studied DNA samples from 410 families with a high incidence of late-onset Alzheimer's, making it the largest Alzheimer's genetics study to date. They found at least four additional gene variations that seem to be linked to a higher likelihood of developing the disease.

What does this mean? Right now, it's too early to warrant genetic testing for these additional gene variations, but it does tell us that the Alzheimer's puzzle is even more complicated than previously imagined. Tanzi suspects there may be dozens of Alzheimer's gene variations yet to be discovered; considering he's one of the world's top experts in genetics and aging, I trust his opinion.

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Alzheimer's Disease Risk Factors

Illustration © Alzheimer's Disease & Referral Center