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Help, My Husband is a Rodent!

Why do some men stray from their marriages, while others seem content to stay with one partner for life?

The answer may come from an unlikely source: the vole. A vole is a rodent, and it comes in several species. Prairie voles mate for life. Mountain voles do not. Research has shown that prairie and mountain voles have different versions, known as “alleles,” of a particular gene (AVPR1A).

Humans have the same gene. In prior studies, certain versions of AVPRIA seemed to be linked in humans to behaviors such as aggression, the age a person first has sexual intercourse, and altruism.

Intrigued by the possibility that AVPRIA may be responsible for vole-like behavior in men, a team of scientists at Sweden’s Karolinska Institute recently conducted an intriguing study.

What they found was that men who have an allele, or gene variant, known as 334 were

  1. Less likely to be married than men who did not have the allele.

  2. More apt to earn lower scores on a partner bonding scale.

  3. Twice as likely to have had a marital crisis in the past year than other men.

The study also found that the wives of men with the 334 allele were much more likely to report dissatisfaction with their marriage.

The study is interesting, but it raises more questions than it answers. For example, it relies on imperfect information such as the definition of a marital crisis. An incident that destroys one marriage might be considered just another fight in another. And asking women to report their level of satisfaction also relies on unreliable reporting.

Then there is the question of interpretation of statistics. The study showed that 30 per cent of 334-men were unmarried. 17 percent of the other men were unmarried. One way to report this information is to say, as the study’s report did, that the 334-men were about twice as likely to be unmarried. Makes them seem like they’re not the marrying type, doesn’t it?

But another way to look at it is that 70 per cent of the 334-men were married – which makes them seem like the marrying type.

This study uses new science to raise on old debate, commonly known as “nature vs. nurture.” In this case, the question is: are men who have the 334 allele simply predestined at birth to be less monogamous? Or are other factors such as cultural background and individual differences as important –- or more important -- in determining whether a man will be a faithful husband?

And most important of all – what should we do with this information? Suppose a genetic screening test were available that could tell parents that they are statistically likely to produce a 334 baby. What action, if any, should they take?

Or suppose that a woman has met a man, and things seem to be warming up romantically. What if she could trot him down to a genetic testing center and find out if he’s a 334? Would that cause her to hand back the engagement ring?

The study’s authors are suggesting no such thing. But inevitably, science is discovering many interesting correlations between human genetics and behavior. What we do with that information is our choice.

Whether the screening is for autism, Down Syndrome, or the 334-allele, it is just as important to know why we want to know genetic information as it is to know what that information is. In the case of severe autism, for example, some couples choose to end the pregnancy. This is a very serious choice and it involves the politics of abortion. But not ending the pregnancy would most likely mean greater-than-average life challenges for the autistic child – and for the family. That is a very private decision, and the question here is, would you rather know, or not know?

With the 334-allele, there are certainly too many “nurture” factors involved to draw any grand conclusions. How men behave in relationships is a complex question, based on such factors as their individual differences, the way parenting was modeled for them at an early age, their previous relationships, the messages the culture and media send about marriage, and much more.

Yet the Swedish study is not meaningless. It does seem to show some linkage. The question for readers is: does it make a difference to you to know if you are -- or are married to -- a prairie vole or a mountain vole?

Note from Ben Kim:

This study brings to mind an Italian study that hit the news wires in 2006, one that found that the hormonal chemistry that creates sexual attraction between new partners tends to fade within two years for the vast majority of people.

The Italian study found that hormones called neutrophins - thought to contribute to feelings of sexual attraction and lust - are at their highest levels within the early stages of a new romance, and are gone within one or two years when two people remain in a mutually monogamous relationship.

Italian researchers also found that as a mutually monogamous relationship extends past the two-year mark, both partners experience an elevation of blood oxytocin, which is thought to generate the desire to "cuddle" when times are good.

As just about every married couple will probably acknowledge, the feelings of intoxication that surround courtship and newlywed status eventually fade.

So why is it that some couples go on to experience rich marriages that last for decades, while others choose to divorce or stay unhappily attached by paper and roof?

There are no easy answers, of course. In some cases, there is enough history of abuse or other displays of contempt to clearly see that it's probably best for both partners to say good bye.

When I think about my own marriage and marriages among family members and close friends, what's abundantly clear is that if both partners are mentally and emotionally stable, there are almost no relationship challenges that two committed people cannot overcome or transcend to allow for a meaningful, love-filled relationship.

For me, it's always been helpful to recall all of the reasons why I want to try my very best to create and maintain a loving and fun marriage. As someone once said, why is often more important than how. If our why is powerful enough, we're likely to find a way.

Please feel free to view either of the following related articles:

Using Honesty to Build a Good Relationship

Some Thoughts on Choosing a Life Partner


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Funny that you did not mention women who cheat. Do they carry the same gene as well? Marriage is either two feet in or two feet out. There is no such thing as a 50/50 marriage. It is 100/100.
Of course relationships ebb and flow but in order to succeed, it must be a daily decision. It means saying I love you to your spouse and I choose to make this work every day. Staying faithful is a choice.
Being happily married is a choice as well. If someone is not happy, they have every right to to make another choice but ending the marriage first is the right way- not cheat. That is cowardly and the most hurtful choice of all.

Seems women tend to be nesters and men tend to be hunter-gatherers. While on the hunt/prowl, they may be distracted by all the women fanning their pretty feathers in their faces.

It has been said that when women cheat, they are vested emotionally and ready to leave. Men cheat sexually, but still "love their wives" - if you believe that.

What I'm curious about is the alcoholism gene - do you have an article on this one? Have there been studies done on children born to alcoholic or addictive parents, yet raised by sober/emotionally stable parents, who became addicts later on in life?