Rare Gene Discourages Alcoholism Among Jews

Study: Jews Have Fewer Problems With Alcohol Dependence

Genetic Diagram
Gene Protects Against Alcoholism. © Getty Images

For many years, it was generally believed that religious and cultural influences were the reason for low rates of alcoholism among Jewish males. This has changed thanks to research which found a biological explanation for the phenomenon.

Gene Has Protective Effect for Alcoholism

Scientists are not exactly sure why, but a particular gene variation tends to discourage heavier drinking in the persons who have it.

The gene was first known as alcohol dehydrogenase 2 (ADH2*2), but later became known as alcohol dehydrogenase 1B (ADH1B), 

An estimated 20 percent of the Jewish population has the ADH1B gene. This is believed to be a factor in the low rates of alcoholism reported in this ethnic group. The gene produces a more active form of the enzyme that catalyzes the first step in alcohol metabolism.

Studies have found that the gene seems to account for the lower rate of alcoholism more so than religious practice. Those who have the gene variant tend to drink less frequently and consume less alcohol. At the same time, they're more likely to have unpleasant reactions to alcohol, which often acts as a deterrent.

Later research found that there is a catch. The protective effects of the gene can be minimized by environmental or cultural factors that encourage heavy alcohol consumption.

Looking at Cultural Influences to Drink

Deborah Hasin, Ph.D., of Columbia University, and her colleagues studied 75 Israeli Jews between the ages of 22 and 65.

They found that the subjects with the ADH1B gene had significantly lower rates of alcohol dependence over their lifetimes.

Hasin's study was the first to link the gene to rates of alcohol dependence, rather than just heavier alcohol consumption. It also found that cultural influences could lessen or negate the gene's protective effects.

The researchers divided the participants into groups based on their country of origin and recency of immigration to Israel. This is where they found variations in the protective effects of ADH1B.

Influences of a Heavy Drinking Culture

The study's subjects were divided into Ashkenazi (those of European background and arrivals from Russia before 1989) and the Sephardics (those of Middle Eastern or North African background) and more recent immigrants from Russia.

The recent Russian immigrants had the highest rates of heavier drinking than the other two groups. They also had the highest rates of past and lifetime alcohol dependency.

The researchers concluded that both genes and environment are factors in the development of alcoholism. Russia has an extremely high rate of alcohol consumption, while Israel has one of the lowest rates. The heavy-drinking culture of the recent Russian immigrants overcame the protective effects of the ADH1B gene. 

Therefore, the Russian immigrants who had been in Israel prior to 1989 were affected by Israel's culture of less alcohol consumption, the research believes. They had rates of alcohol dependence similar to the Ashkenazis and Sephardics.

Younger Israelis Influenced to Drink

In recent years, however, the Israel culture has changed to include higher levels of alcohol consumption.

In particular, heavy drinking has increased among younger Israeli Jews.

A later study by Hasin and colleagues looked at the differences in the effect of the ADH1B gene on the alcohol consumption of younger and older adult Israelis. Drinking levels among older participants were low, regardless of the type of ADH1B gene. Yet, in younger Israelis, those without the protective gene had greater rates of alcohol consumption.

Overall, those over 33 years old had lower drinking rates than those younger than 33. This indicates the environmental influences promoting greater drinking among younger Israelis can overcome the protective effects of the gene.

Source:

Abrahams D. Rare Form of Gene Discourages Alcohol Dependence Among Jews. Center for Advancing Health. 2002.

Neumark YD, et al. Alcohol Dehydrogenase Polymorphisms Influence Alcohol-Elimination Rates in a Male Jewish Population. Alcoholism Clinical and Experimental Research Journal. 2004;28(1):10-4.

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