Genetics could be the reason you’re a lightweight drinker, study says

Posted at 6:23 PM, Sep 06, 2016

PULLMAN, Wash. – If you’ve ever wondered why some people get drunk in an instant, the answer is genetics, according to researchers at Washington State University.

They say a receptor in our brain affects our reaction to alcohol.

The protein receptor, located on cells in the cerebellum, is known as GABAA.

When it’s activated, it suppresses the firing of brain cells. That leads to balance issues, stumbling, slurred speech and reduced social inhibitions.

Lightweight drinkers have receptors that overreact to even the smallest amount of alcohol.

For others, the receptor takes a long time to be stimulated. This can lead to binge drinking and alcoholism.

Researchers think increasing the receptor’s sensitivity could prevent people from drinking too much.

“It takes them from drinking the equivalent of three to four units of alcohol in one to two hours, down to one to two units,” said David Rossi, a Washington State University assistant professor of neuroscience.

After testing their hypotheses on mice, researchers believe therapy could be used to curb excessive drinking.

Those bred to have a sensitive receptor had trouble staying on a rotating cylinder after consuming the human equivalent of one or two drinks.

Those bred to be desensitized could stay on after drinking three times as much alcohol.

The study found those who got drunk quicker were more likely to stop drinking sooner.

“It mirrors the human situation,” said Rossi. “If you’re sensitive to the motor-impairing effects of alcohol, you don’t tend to drink much. If you’re not sensitive, you drink more.”

Researchers injected a drug called THIP into the cerebellum of the mice that were less sensitive alcohol.

The drug activates the GABAA receptor, mimicking what happens to those with alcohol-sensitive receptors. It ended up deterring the mice from drinking.