Yet another friend of mine has been afflicted by this seemingly modern-day malaise: a cheating husband.

The story follows the usual plot lines: he had been cheating on her for several months, during which time he had suddenly become 'super busy' at work and even had to be away - ahem - for weekends at a stretch. She never suspected a thing until, that is, she caught him out.

At first he denied it, claiming "it's not what you think it is". Then, when cornered with evidence, he claimed (cough, choke) that this other lassie "had nothing to do with the breakdown of the marriage". No, no, no, he said, holding on tightly to his halo: the affair was not the cause of the breakdown; it was just a "symptom of their unfulfilling eight-year-old marriage".

And with those words, he moved out of the family home, straight into his mistress's arms, unfrazzled by the pitiful wreckage left behind.

Now I am very much aware there are women who cheat as well. But to be honest, the stats speak for themselves - from a quick straw poll with acquaintances, for every woman cheat there are 10 men.

Also, I do not want to moralise: I am very much aware that anybody is capable of just about anything when it comes to love and desire - even the most stubborn of loyalties are constantly being challenged.

And I am also aware there are two types of cheat: those who, once caught out, are truly sorry for the pain caused by their actions and honestly repent and strive hard to redeem their actions; and those who genuinely believe their bamboozling cannot possibly qualify as 'cheating' and that it was actually carried out for the well-being of humankind. Needless to say, they're the ones who would never utter a whispered apology for wreaking havoc.

But my question here is, why the cheating? Why don't guys with a wandering eye admit their temptations to their partner right before the cheating bit? Wouldn't that make life for all parties concerned much easier?

There won't be any need for stressful lying and scheming, which is, by the way, quite a serious health risk. A study at the University of Turin found that patients most at risk from migraines and fatal aneurysms were men having affairs.

Incidentally, this month's Men's Health Magazine, dubbed 'The Cheating Issue', asks: "Adultery is largely vilified by society, but what if the occasional well-timed dalliance could improve your life?" It claims that man's evolution is proof enough that monogamy is a relatively modern social construct.

This statement possibly has its roots in the famous 'cads or dads' theory, which suggests there are two sorts of men in this world: those who are meant to father children and those who are meant to raise children. The former are promiscuous, the latter are constant.

Just to put you in the picture for cads, think Tiger Woods. And Ashley Cole and John Terry and, well, the whole of the Chelsea Team School of Fidelity, who really need to notch up some rigorous training on how to behave.

Apparently, being a cad or a dad has nothing to do with celebrity statuses or the money earned. For dads, one can come up with equally famous high-earners. Think Jamie Oliver, Johnny Depp or Pierce Brosnan. Locally, and I know they're not exactly Generation X, Ċensu Tabone and Eddie Fenech Adami, spring to mind.

According to evolutionary biologists, the cheating phenomenon can actually be broken down to the level of DNA. Apparently there's this critical little chemical variation in the male of the species called the 'vasopressin receptor gene'.

Men who have this gene tend to be trustworthy and reliable partners, sticking with one spouse for decades, raising children and running stable households. Men who lack this gene on the other hand are prone to dalliance and disloyalty, always needing to seek sexual variety elsewhere.

Of course, the problem is that cads are often charming but heart-splintering. The others are a bundle of steadfastness, but perhaps a bit less, er, mesmerising.

Evolutionary psychologist Professor Bill von Hippel, at the University of Queensland says for long- term relationships, women tend to choose a more reliable man, but sometimes they are blinded by the daring and passionate characters. Duh. Go figure.

My plea, if we are to assume that cheating is biological, is: can someone invent a gadget which would bleep the nosiest dance-floor down, the minute a gene-lacking lad approaches?

krischetcuti@gmail.com