The gene that helps understand why people keep drinking alcohol while others control their intake after a drink or two has been identified, researchers announced on Monday.

The gene, beta-Klotho, was found through an international study by UT Southwestern Medical Center researchers and scientists in Europe. The study looked at records of more than 105,000 light and heavy social drinkers.

Beta-Klotho decreases the amount of alcohol intake, researchers say. 

“The study identified a variation in the β-Klotho gene linked to the regulation of social alcohol consumption. The less frequent variant, seen in approximately 40 percent of the people in this study, is associated with a decreased desire to drink alcohol,” said Dr. David Mangelsdorf, Chair of Pharmacology at UT Southwestern and the study’s co-author.

Excessive alcohol consumption causes more than 3 million deaths annually worldwide, but previous studies on that issue mostly focused on addiction.

For they study, heavy drinking was considered as more than 21 drinks weekly for men and more than 14 drinks per week for women. Light drinking was defined as 14 drinks or less per week for males and seven drinks or less per week for females. A “drink” was equal to a small glass or wine, or a half pint of beer.

Researchers believe they have found a link with the beta-Klotho gene, and that it works along with other genes called FGF21 and FGF19.  

“The gene in the current study seems to work via a feedback circuit that goes from the liver, which processes alcohol, to the brain, where β-Klotho and classic FGF21 receptors form a cellular machine, or receptor complex, which binds to the liver hormone FGF21 to signal the response to alcohol,” Mangelsdorf said.

Researchers conducted experiments in mice to learn more about the gene’s role in alcohol drinking behavior.

In the study, mice that were genetically unable to produce the beta-Klotho gene were given the choice of water and alcohol. Researchers found that the genetically altered mice chose alcohol even when they given the FGF21 gene, which suggests that the hormone’s ability to repress the preference for alcohol depends on whether beta-Klotho is present.

“The current study suggests that the FGF21-β-Klotho pathway regulates alcohol consumption in humans and seems to point to a mechanism that we might be able to influence in order to reduce alcohol intake,” said Mangelsdorf.

The study could lead to the development of drugs that can control alcohol consumption, even in people that suffer from alcoholism, researchers hope. Heavy alcohol consumption is linked to two heart disease risk factors, especially high blood pressure and obesity, according to the American Heart Association.

The study was published in the Proceedings of the National Academy of Sciences.