The reason a person is happily or dismally married may reside in their DNA. According to researchers based at the University of California, Berkeley, it matters whether that person possesses short or long variants of the serotonin transporter gene, the so-called happy hormone.
The researchers found that the 5-HTTLPR polymorphism moderates the association between negative and positive emotional behavior and changes in marital satisfaction over time. As it turns out, the marital effect is indirect—that is, the genetic variation determines how sensitively marital satisfaction depends on emotion behavior.
Individuals who possess two short alleles and evidence higher negative and lower positive behavior are more likely to experience declines in marital satisfaction over time. But if these individuals evidence low levels of negative or high levels of positive emotion, they experience the highest levels of marital satisfaction. In other words, they are more likely to suffer in a bad marriage and thrive in a good one.
The researchers, who published their results October 7 in Emotion, entitled their report “The 5-HTTLPR Polymorphism in the Serotonin Transporter Gene Moderates the Association Between Emotional Behavior and Changes in Marital Satisfaction Over Time.” They based their study on data from a 13-year longitudinal study of more than 150 middle-aged and older adults in long-term marriages.
In assessing emotional behavior, the researchers objectively measured the actions of couples who visited UC Berkeley every five years to report on their marital satisfaction and interact with one another in a lab setting. The researchers coded their conversations based on facial expressions, body language, tone of voice, and topic of discussion.
“We are always trying to understand the recipe for a good relationship, and emotion keeps coming up as an important ingredient,” said the report’s senior author, Robert W. Levenson, Ph.D., professor of psychology at UC Berkeley and director of the Institute for Personality and Social Research, in comments circulated by the UC Berkeley News Center. “With these new genetic findings, we now understand much more about what determines just how important emotions are for different people."
Emotional behavior did not predict changes in marital satisfaction in individuals who possessed one or two long alleles. According to the researchers, whatever combination of alleles was considered, the effects of the combination were still apparent even after depression and other covariates were taken into account.
As indicated by another comment attributed to Dr. Levenson, the link between genes, emotion, and marital satisfaction was particularly pronounced for older adults: “One explanation for this latter finding is that in late life—just as in early childhood—we are maximally susceptible to the influences of our genes.”