SAN FRANCISCO (KCBS) – While Alzheimer’s has mainly been thought of as a disease of the old, new research out of California has found that a gene may actually damage a person’s brain 50 years prior to being diagnosed with the disease.

Scientists already know that one of the things that causes Alzheimer’s Disease is the accumulation of deposits in the brain called amyloid plaques, which seem to damage your brain’s wiring, preventing different parts of your brain from communicating with each other.

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“We know that there’s a slow erosion of the brain from an army of culprits. There’s a lot of genes that we have that slightly increase your risk or slightly reduce your risk,” said Paul Thompson, a professor of neurology at UCLA.

KCBS’ Rebecca Corral Reports:

He said two years ago, a gene was discovered called clusterin, or CLU, that increases the risk of Alzheimer’s by about 20 percent.

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“We really didn’t know what this gene does. This is the first study to see what this gene does to the brain,” said Thompson. “One of the big surprises is that it actually damages your brain when you’re young. So you’ll see deficits in brain scans as young as the age of 20 or so.”

And Thompson said this gene does its work silently, without any outside symptoms.

“When you think about what your genes are doing, this slow battle going on in your brain is eroding brain tissue,” he said. “But you wouldn’t begin to see any signs of memory loss or impairment mentally until your 60s or 70s. By that time, a lot of the brain tissue would actually have been irreversibly removed.”

Thompson said it would be helpful to know if you have the gene that makes you vulnerable to Alzheimer’s because you can start taking steps to either slow down or ward off the disease.

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