Cheating Genes

September 2, 2008 - Scientists (Hasse Walum) at Karolinska Institutet have found a link between a specific gene and the way men bond to their partners. The results, which are presented in the scientific journal PNAS, can lead to a better understanding of such problems as autism and social phobia. Hasse Walum and his colleagues made use of data from The Twin and Offspring Study in Sweden, which includes over 550 twins and their partners or spouses. The gene under study codes for one of the receptors for vasopressin, a hormone found in the brains of most mammals. The team found that men who carry one or two copies of a variant of this gene *334* often behave differently in relationships than men who lack this gene variant. The incidence of 334 was statistically linked to how strong a bond a man felt he had with his partner. Men who had two copies of 334 were also twice as likely to have had a marital or relational crisis in the past year than those who lacked the gene variant. There was also a correlation between the men's gene variant and what their respective partners thought about their relationship. "Women married to men who carry one or two copies of 334 were, on average, less satisfied with their relationship than women married to men who didn't carry this allele", says Hasse Walum.