Great news. No sarcasm. Guys have a genetic disposition toward cheating. According to a study recently published in the Proceedings Of the National Academy of Sciences (a very official sounding document), “Men are more likely to be devoted and loyal husbands when they lack a particular variant of a gene that influences brain activity.”

I know. Wow.

The gene variant – which has a weird name – is present in two of every five men. Yes, that’s 40%. In studies men with two copies of the allele (thank you seventh grade bio) had twice the risk of experiencing marital dysfunction compared to men carrying one or no copies (I can’t do that math).

The allele studied regulates the activity of a hormone in the brain that acts as a sort of key to a lock box. Inside that lock box – the desire to cheat (and whatever Al Gore put in there). So men with two keys (two of the alleles) are more likely to get that box open. Doesn’t mean they’ll make the move to open it, but it’s there – taunting.

Why study men and not women? Because the hormone being examined is known to play a larger role in the brains of men vs. women. Sorry.

So why is this great news, no sarcasm? Two reasons.

It confirms that rage-inducing maxim: “once a cheater, always a cheater.” People tend to be touchy about that phrase. Like they feel about, “all girls turn into their mothers.” With cheating based in the genetic code we can just say “born a cheater, always a cheater” and, girls share ½ their mother’s genes it should just be “all girls are already their mothers”. Nice to have that settled once and for all.

We may some day be able to test for the cheating gene in men. Yes, weird. Sure, dangerous. But no doubt helpful. Just because a guy could cheat doesn’t mean he will (according to both logic and this study), but at least you’d know what you were getting involved with. It would be like having the chance to interview every girl a guy ever dated before you make a decision on him – sort of.

Of course it does leave you wondering what else is pre-imprinted on the genetic code, for both guys and girls. I’d like to propose we do some research into the following:

-complete and utter ability to apologize
-tendency to say, “what do you want from me” as an attempted close to every argument
-stalker-like cell phone, blackberry, email, and Facebook
-whining

You decide to which side they apply.