FRIDAY, Nov. 12 (HealthDay News) -- A minor gene variation may be associated with altruism, an unselfish concern for the welfare of others, a new study has found.

In a recent experiment, Martin Reuter, of the University of Bonn in Germany, and colleagues found that people with this variation in a gene known as COMT gave away twice as much money on average to a charitable cause than people with another variation of the gene.

The COMT gene contains building instructions for an enzyme that acts upon dopamine (which is associated with positive emotions) and certain other chemical messengers in the brain. There are two variants of the COMT gene: COMT-Val and COMT-Met. They occur with about the same frequency in people.

The variants differ in only a single building block. But in people with the COMT-Val variant, the associated enzyme works up to four times more effectively, the study authors explained in a university news release.

And in an experiment involving prize money and the chance to donate it to charity, people with the COMT-Val variant were twice as likely to donate it as were people with the COMT-Met gene, the German researchers found.

This is the first time that scientists have been able to find a possible link between a particular gene and altruism.

The study findings are published in the current online edition of the journal Social Cognitive and Affective Neuroscience.

More information

For more on altruism, visit the archives of the American Psychological Association.