Religiosity can moderate genetic effects on alcohol use problem during adolescence, says a new study.

The heriditory of an alcohol-related phenotype (measurable and/or observable traits or behaviours) depends upon the social environment within which it is measured, such as urbanicity, marital status, or religiosity.

"People with a religious background may be less likely to express alcohol-related phenotypes than those from nonreligious backgrounds. Furthermore, the influence of genes on these phenotypes also varies according to social background. We also know that genes play a more important role in alcohol-related phenotypes in people from urban backgrounds, unmarried women, and nonreligious individuals than those from rural backgrounds, married women, or those with a religious upbringing," says Tanya MM Button, a postdoctoral fellow at the University of Colorado at Boulder and corresponding author for the study.

Button and her colleagues examined 1,432 twin pairs: categorized as identical or monozygotic (MZ) if they had similar physical characteristics and were concordant on all markers; and fraternal or dizygotic (DZ) if they presented with dissimilar physical characteristics and were discordant on any of the markers.

"Our study showed that genetic factors could influence problem alcohol use more in nonreligious adolescents than adolescents with a greater religious outlook," said Button.

"Thus, adolescents who are raised to value religious concepts are less likely to develop problems with alcohol use, even in the presence of a genetic predisposition for doing so," she concluded.

Results will be published in the September 2010 issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.