A new study may be the first to link genetics and emotion to marital satisfaction, suggesting that certain variants in a spouse's genes factors into how happy, or not, their marriage is.
Writing in the journal Emotion, senior author and University of California Berkeley psychologist Robert Levenson suggests that a gene involved in the regulation of serotonin can predict how much emotion affects our relationships.
The genetic analysis focused on a specific allele, or gene variant, known as 5-HTTLPR. All humans inherit a copy of this allele from each parent.
"An enduring mystery is, what makes one spouse so attuned to the emotional climate in a marriage, and another so oblivious?" Levenson said. "With these new genetic findings, we now understand much more about what determines just how important emotions are for different people."
A 20 year longitudinal study of more than 150 married couples provided Levenson and his team with plenty of study participants.
The researchers found that people with two short 5-HTTLPR alleles were the most unhappy in their marriages when negative emotions like contempt and anger were present, and most happy when there were positive emotions present in the relationship.
Study participants whose two 5-HTTLPR alleles were longer were much less bothered by the emotional tenor of their marriages.
"We are always trying to understand the recipe for a good relationship, and emotion keeps coming up as an important ingredient," Levenson said.
The study suggests that people with two short alleles are likely to suffer in a bad relationship and thrive in a good one.
"Individuals with two short alleles of the gene variant may be like hothouse flowers, blossoming in a marriage when the emotional climate is good and withering when it is bad," said Claudia M. Haase, assistant professor of human development and social policy at Northwestern University and lead author of the study. "Conversely, people with one or two long alleles are less sensitive to the emotional climate."
"Neither of these genetic variants is inherently good or bad," Haase added. "Each has its advantages and disadvantages."
Seventeen percent of the spouses studies had two short 5-HTTLPR alleles, while 83 percent had one or two long alleles. Those with two short alleles presented a strong correlation between the emotional tone of their conversations and how they felt about their marriages, while the other 83 percent said that the emotional quality of conversation with their spouse bore little or no relation to their marital satisfaction.
In older adults, the connection between genes, emotion and marital satisfaction is was the most pronounced.
"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," Levenson said.