Some men have an easier time being married than others. Now we learn DNA plays a big part in marriage.
A brain hormone called vasopressin influences men's bonding with a sex partner. More vasopressin makes men feel closer and want to stick around. Hasse Walum at the Karolinska Institute in Sweden and his research team report on the effects of a variation in the gene that determines the placement of vasopressin receptors in the brain.
Around 40% of all men inherit this variant from one or both parents. In this study of Swedish men, one copy increases the likelihood that a man will avoid marrying his partner or experience marriage problems big enough to make him consider leaving. Two copies increases it again, to more than double the divorce risk for men with no copies and more than one-third considering divorce each year.
Does this mean their marriages (or their wives) are doomed? Not at all. It means men with this genetic makeup need some way other than fleeting emotions to advise them on whether it's worth fixing a problem instead of walking out or starting an affair. For them, it can be very important to assume love and take a second look before acting on their initial, emotional interpretation of an incident.
I am sure others will claim, once again, that this is proof we're not meant to marry for life, that we should just move on -- or have an affair -- when the sex gets stale or we disagree. I think watching a little boy whose father has just moved out, a teenage girl who never knew her father, or a pair of 85 year-olds helping each other enjoy life makes it clear we humans have many excellent reasons to bond.
For more on the study, see The Washington Post or Bloomberg.