Genes could help determine who is at risk for Alzheimer’s

More than 6.7 million Americans are living with Alzheimer’s disease. Memory loss is often the first sign but decades before people begin to fade away, their brain starts to show signs of changes.

Breakthrough research examines how one gene may be the key to early diagnosis.

Actor Chris Hemsworth is known as the indestructible Thor, but in real life, even the strongest can be struck down by the debilitating disease.

Hemsworth has two copies of APOE4, a set from his mom and a set from his dad, according to the show Disney+ show “Limitless.”

“That means you have an increased risk of Alzheimer’s disease,” a doctor on the show tells him.

Researchers believe this gene is important in laying down myelin, which is a protein that insulates neurons in the brain.

“If you happen to be lucky and get an E2 form of it, you have slight protection against Alzheimer’s disease,” said Dr. Gordon. “If you have this one that’s an E4 polymorphism, your risk of developing Alzheimer’s disease goes up about fourfold– if you have one copy and about twelvefold if you have two copies of this gene.”

Researchers want to know what it is about the gene that’s leading to an elevated risk.

“The first domino that falls is this protein called amyloid, begins building up in the brain, and this is a slow progression,” Gordon said.

You can see the progression of plaque over a decade.

“What you can see is the amyloid has built up even more, and now this person is mildly demented. They’re at that earliest stage of dementia,” Gordon said.

And by learning why some people are protected and some are not, it could lead to new treatments to stop the progression of the disease before any signs or symptoms appear.

The research also shows that there is a difference between men and women when it comes to how the APOE gene impacts them. For men, an APOE3 and APOE4 gene didn’t have a huge effect on their symptoms, while in women, it did.

That may be the reason researchers believe men seem to now show signs sooner, and although women’s symptoms may appear later, the symptoms seem to strike stronger, and women decline faster.