According to a recent research, the gene that controls the hormone vasopressin and is responsible for monogamy in prairie voles – which are studied for their human-like social qualities – also plays a role in human relationships.

Researchers from the Karolinska Institute in Stockholm, Sweden, ran genetic tests on 2,186 participants in Sweden’s “Twin and Offspring Study.” They were given questionnaires, visited at home by researchers, and had DNA tests.

Men with a certain variation of the AVPR1A gene, which affects neuropeptide arginine vasopressin, a brain chemical, causing blood pressure disturbances – got low scores on the bonding test and were not as likely to be married as men who did not have that gene variation.

The results of the study were published in the National Academy of Sciences. When women were asked about the quality of their marriage, those who were married with men who had one or two copies of the gene variation scored significantly lower on a scale of partner bonding.

Women who said they were satisfied with their marriages were married with men who didn’t have the gene variation.

Overall, 30% of the men who carried the gene variant were unmarried.

The study contributes to the results of other studies that examine the link between the hormone vasopressin and disorders such as autism and social phobia.

“This doesn’t explain how you succeed in a relationship,” said Paul Lichtenstein, a professor of genetic epidemiology, who led the study. “It gives you a predisposition, but it doesn’t determine how successful you will be in marriage.”