The chemistry of commitment

Parker-Pope does an interesting article on a topic that has repeatedly appeared in this blog, the role of vasopressin in regulating affiliative behavior. Here she notes studies on correlations between a gene regulating vasopressin activity and commitment and marital stability. Studies on 552 sets of twins found:

...men who carried a variation in the gene were less likely to be married, and those who had wed were more likely to have had serious marital problems and unhappy wives. Among men who carried two copies of the gene variant, about a third had experienced a serious relationship crisis in the past year, double the number seen in the men who did not carry the variant.

Parker-Pope also notes experiments suggesting that women might have developed a kind of early warning system to alert them to relationship threats.