Genes Play Role in How Alcohol Affects Men and Women

Aug. 15, 2011 -- New genetic research may help explain some of the different ways that alcoholism affects men and women.

Gender differences in alcoholism have previously been attributed to differences in size and body composition. But the new study suggests that genes may also play a role in the way men and women react to alcohol.

The study is published in Alcoholism: Clinical & Experimental Research.

The presence of two genes, ADH1B and ALDH2, increases risk for alcoholism.  But men and women differ when it comes to how these genes affect risk.

An inactive ALDH2 gene actually delays the development of alcoholism among men. But in women, it may accelerate it, according to the study.

The study results suggest that gender differences in the effect of the ADH1B and ALDH2 genes may be helpful in predicting the course of alcohol dependence, says study researcher Mitsuru Kimura, MD, PhD, of the Kurihama Alcoholism Center in Kanagawa, Japan, in an email.

Genetic Influences on Alcoholism

ADH1B and ALDH2 act to eliminate most of the alcohol taken into the body. But a lack of ALDH2 activity causes a flushing response due to drinking alcohol. This response is characterized by flushing, nausea, and a headache and tends to greatly suppress drinking.

In the new study of 415 men and 200 women who were hospitalized for alcoholism at the Kurihama Alcoholism Center, female alcoholics with inactive ALDH2 were more likely to have psychiatric disorders such as depression and anxiety than women with the active version.

This may drive certain women towards dangerous drinking despite the flushing response, the researchers suggest.

Women with inactive ALDH2 also tend to develop alcoholism earlier than women with the active version of the gene. In contrast, ALDH2 does not seem to affect age of onset of alcoholism among men.

"There are male/female differences in alcohol use rates and addiction rates, but this was thought to be due to differences in size, but this paper suggests that it has to do with metabolism as well," says Victor M. Hesselbrock, PhD, a professor of psychiatry at the University of Connecticut School of Medicine in Farmington, Conn.

The new findings may help develop more targeted treatments for alcoholism that take both genes and gender into account, he says.

"Gender and genetic differences can put you at risk even without realizing it," says Harold C. Urschel, MD, an addiction expert in Dallas.