The National Institutes of Health
From NIH News in Health (NIH)
September 26, 2011
Why can some people make it through difficult times with little trouble while others crumble under the same circumstances? A new study suggests that the answer lies-at least in part-in your genes.
Scientists have long known that people with certain psychological traits, or resources, can fare better in challenging situations. Three of the most widely studied psychological resources-optimism, self-esteem and mastery (the feeling that you can master your environment and achieve what you want)-are good predictors of a person's physical and psychological health. These 3 resources have been shown to help people weather stressful events and beat back depression. Because these psychological resources tend to run in families, scientists had suspected a genetic component.
Earlier studies found evidence that particular variants, or alleles, of the OXTR gene might be linked to stress-related traits and other psychological characteristics. OXTR codes for the receptor for oxytocin, a hormone that contributes to positive emotion and social bonding.
Dr. Shelley E. Taylor and Shimon Saphire-Bernstein of the University of California, Los Angeles, and their colleagues set out to determine if these OXTR alleles might also contribute to optimism, mastery and self esteem. The scientists asked 326 volunteers to complete questionnaires that measured the 3 psychological resources and also assessed depressive symptoms. The researchers analyzed the DNA from the participants' saliva to find variations in the OXTR gene. The study was funded by NIH's National Institute on Aging (NIA) and the National Science Foundation.
As reported on September 13, 2011, in the Proceedings of the National Academy of Sciences, the researchers found that people who had 1 or 2 copies of the OXTR gene with an "A" (adenine) allele at a particular location tended to have more negative measurements than those with 2 copies of the "G" (guanine) allele. People with an A allele were less optimistic, had lower self-esteem and felt less personal mastery than people with 2 G alleles. In addition, the A allele was linked to higher levels of depressive symptoms. Follow-up analyses suggested that the effects of OXTR variants on depression are largely mediated by the gene's influence on psychological resources.
The scientists say their findings are the first to link OXTR directly to specific psychological resources. But the gene itself is far from the only factor influencing these traits.
"Some people think genes are destiny, that if you have a specific gene, then you will have a particular outcome. That is definitely not the case," says Taylor. "This gene is one factor that influences psychological resources and depression, but there is plenty of room for environmental factors as well."
The researchers are now planning studies to search for additional genes that might work with OXTR to affect behavior and responses to stress.
-by Vicki Contie