FYI Daily

Memory Trouble? Blame Your Genes, Exercise More

Last updated: Oct 26, 2011


One small change in one specific gene may determine how quickly you'll lose your marbles, according to Ahmad Salehi, M.D., PhD at Stanford.

Salehi and his colleagues followed 144 healthy male pilots over age 40, some professionals and some amateurs, for two years. During that time, each pilot showed up three times to perform a flight simulation called the Standard Flight Simulator Score.

This isn't a kid's video game -- it's an FAA-approved, 75-minute simulation with air traffic controllers, other simulated planes, and various emergency situations to deal with. The pilots each got several practice runs a few weeks before their test flights. The simulations were scored on various criteria, including reaction times and deviations from the ideal altitude and speed of the simulated airplane.

The pilots also provided saliva or blood samples so they could be genotyped. The researchers were looking for the gene that regulates brain-derived neurotropic factor (BDNF), a protein that helps maintain the central nervous system. About half of the pilots had a version of the gene dubbed the "val" version (because the BDNF protein contains valine in a particular place in those individuals), and the rest had a version called the "met" version (because the BDNF protein contains methionine instead of valine in those individuals).

The met version of that gene has already been linked to several health risks, including depression, anxiety disorders, and stroke. Now, it's been linked to decreased cognitive function as well.

Salehi found that, while everyone's scores dropped over the two years, the met group's scores dropped twice as fast as those of the val group.

Now, before you head out to get genotyped, remember this: Lifestyle choices sometimes matter more than genes. And in this case, there's a particularly important lifestyle change to be made.

"The one clearly established way to ensure increased BDNF levels in your brain is physical activity," Salehi said.

Anyone up for a walk?