Why some people are more susceptible to developing drinking problems? Study Finds

They then exposed these two groups of cells, one from the people with a high genetic risk for alcohol use disorder and one from the people with a low risk of alcohol use disorder, to alcohol levels that mimicked those seen in the blood following alcohol use.

"The microglia with the high genetic risk scores were far more active than the microglia with the low genetic risk scores after the alcohol exposure," said Xindi Li, lead author of the study, a postdoctoral fellow at the Child Health Institute of New Jersey.

The highly active cells engaged in more "synaptic pruning" -- removing connections between neurons in the brain. This increased pruning activity could have significant implications, the researchers said.

"After many years of drinking, people with these genetics may have a greater risk of dementia because the microglia pruned so many more connections," Li said.

"Their overactivity could make neurons less functional."

This work could eventually lead to better treatments for alcohol use disorder. The results suggest that if different genetic variations lead to different cell behavior in the brain, people with different genetic signatures may need different treatments.