Envision a married couple. Now, pretend that things haven’t been going so well in that marriage, possibly due to boredom or dwindling intimacy between the husband and wife. We’ll say that this has been going on for quite some time. Would you predict that the woman or man would be most inclined to cheat?

Many would automatically assume the man.

Several biologists, for example, argue that men cheat more due to the instinct to spread their genetic seed, whereas women usually want one mate in order to have protection and support. This Darwinian credence has long been accepted in society, influencing a seemingly natural “truth” about the sexes: men play and women get played.

Even statistics appear to confirm that men cheat more often. For example, the 2002 issue of Journal of Couple & Relationship Therapy by Joan D. Atwood and Limor Schwartz argues that 45-55% of married women had admitted to engaging in extramarital sex at some point during their relationship compared to 50-60% of married men.

Possibly, these biology-based belief systems and statistics are what encouraged the recent study that claimed to “prove” there is – what an overwhelming amount of media coverage is calling – a “male cheating gene”.

In the September 2008 Timesonline.co.uk article, “Scientists uncover genetic variant which make some males prone to infidelity” by Mark Henderson, research found that this gene (known as allele 334) affects the receptor for the hormone vasopressin, which plays a large role in sexual attachment, pair-bonding and social behaviour.

The effects of vasopressin were first distinguished in 2004 by studying different species of voles (small mouse-like rodents of the family Cricetidae). Research found that, although meadow and prairie voles are cousin species, their sexual behaviour is significantly different.

Male prairie voles are monogamous, where male meadow voles – like most mammals – are extremely promiscuous.

The article explained that when a male and a female prairie vole meet, “the two indulge in 24 to 36 hours of nearly continuous mating, which cements a bond that invariably lasts for life.” If one partner dies, the survivor most always remains celibate.

It was argued that this monogamy is directly related to the fact that male prairie voles’ brains contain higher levels of vasopressin than those of meadow voles. After this study, scientists discovered that vasopressin is also active in the human brain. Since then, many have questioned whether it might play a similar role in human relationships.

In 2008, behavioural geneticist Ph.D. student at the Karolinska Institute in Stockholm, Hasse Walum, and a team of scientists investigated three genetic variations in the human vasopressin receptor and tested a database of 2,186 twins and their partners to determine which types they had inherited.

Published in the journal Proceedings of the National Academy of Sciences (vol. 105 issue 37), the study argues that men are more likely to be “devoted” and “loyal” husbands when they lack allele 334.

They found that about 40% of men have one or two copies of allele 334 – men with two copies had a greater risk of “marital discord” than men with one copy, and men with one copy of the gene were at more risk of such discord than men with no copies (the scientists claimed to have only looked at men because the hormone is known to play a larger role in their brains than in women’s).

“Men with two copies had twice the risk of experiencing marital dysfunction with a threat of divorce during the last year compared to men carrying one or no copies,” Walum was quoted in many publications. “Women married to men with one or two copies of the allele scored lower on average on how satisfied they were with the relationship compared to women married to men with no copies.”

Gary Neuman, a psychotherapist and marital therapist in the United States for 20 years, was also interested to discover why men cheat. In his book The Truth about Cheating (2008), Neuman interviewed 200 men from 48 states, including 100 men who had cheated and 100 who had not, and countered Walum’s research, concluding that genetics had little to do with infidelity and marital collapse. His book reveals that more men blame an “emotional disconnect” in their marriage as the central reason they feel the need to find another partner; not necessarily better or more intercourse.

“Women have been made to believe that the emotional part of the relationship is not as crucial to men,” Neuman was quoted in a September 2008 Timesonline.co.uk article by Alexandra Blair. “But I found that they are highly emotional and that only when they feel disconnected do they begin to stray.”

Neuman found that only 8% of those men questioned blamed sexual dissatisfaction as the sole reason for their infidelity. Additionally, 77% of men who cheated had best friends who were unfaithful as opposed to those who remained loyal.

Even though he has little commiseration for those who blame genes for cheating, after his study Neuman admitted that, for some of the unfaithful men, little could have been done to prevent them from straying – 12% said that they would have cheated no matter what.

After considering the biological research behind the “male cheating gene” and Neuman’s investigation on emotional factors within a marriage, a notion kept running through my head: Women cheat too. Yes, statistics show that men admit to cheating more than women, but I couldn’t help but wonder where the research on societal and cultural factors was – where the research on women was.

Throughout history, infidelity has been classified as an “instinct” or the “nature” of men. Since men were usually designated to the public sphere and women to the private, if a husband went astray, it was the wife’s fault for not balancing the relationship (since marriage was deemed as a personal affair).

Because it was assumed that woman’s “nature” was to maintain the power of sensibility, feminine sexuality and promiscuity has always been more frowned upon. Current studies trying to prove that there is purely a biological reason behind infidelity in men are merely making a convenient excuse for them to cheat – as in the past, men can write it off as their “nature”.

The official figures for 2007 revealed that the divorce rate in England and Wales fell to 11.9 per 1,000 married people in 2007 from 12.2 per 1,000 in 2006. Interestingly, according to figures from the Office for National Statistics, more than twice as many women initiate a divorce as men. In 2005, 96,855 women filed for divorce compared with 44,583 men. Of those, 17,915 women cited adultery as the main reason for divorce compared with 10,077 men.

So, what do these statistics mean?

Possibly women felt more societal pressure in the past to suppress their sexual desires than today? Maybe it is just as much a woman’s “nature” to cheat as it is man’s? Or perhaps, second chances are given to men more than women?

Whatever the case, current research that only looks at biology as a definitive “proof” that males are more prone to have a wandering eye is not sufficient. Only until a mix of nature and nurture (biological, emotional and social) is considered when researching both men and women can people begin to envision an accurate portrayal of infidelity patterns.

Originally Published Sunday, March 8, 2009 in UK publication, Seven Magazine