Kissing cousins: Is "Genetic Sexual Attraction" a real phenomenon?



Readers were shocked to hear about John and Jenny Deaves, the real-life Australian couple and father/daughter who had a child together. And as twisted as their partnership seems, it turns out that incest may be more common than you think due to a very real phenomenon described by scientists as GSA, or Genetic Sexual Attraction.

There have been many studies that show that humans are almost subconsciously drawn to mates with DNA makeup that is similar to their own:

"A new study by psychologists at the University of St Andrews shows that men and women are more likely to choose a spouse whose eye, skin and hair colour resembles that of their opposite-sex parent. Last year, a study by the same team revealed that women with older fathers, and men with older mothers, are usually attracted to older-looking partners. The same principle applies to racial characteristics, and to the smell of an opposite-sex parent. Although the reasons are unclear, one theory is that we are "imprinted" from birth with certain familiar characteristics with which we feel comfortable and to which we are eventually attracted."--The Guardian

But the level of just how similar can be extreme in some cases. The reason that we're not naturally attracted to our brothers or sisters is due to the "Westermarck effect," a theory named after the scientist Edward Westermarck, who hypothesized that "overfamiliarity and boredom automatically caused siblings and other close relatives raised together to go out of their way to avoid sexual contact. Westermarck also reasoned that, since we find the idea of sex with our relatives so distasteful, we developed moral codes and laws to ensure that society conformed to this 'norm' to avoid any social disruption, shame or discrimination." The exception to the rule seems to occur in cases where relations are separated at childhood, thus missing that imprint, and re-united later in life. Think Oedipus.

Although GSA is a phenom that isn't exactly taught in biology classes, some scientists, and the people who suffer from it, insist it's very real. There's even a web site that seems to serve as a kind of support group for those that are outspoken about its socially and emotionally crippling complexities.

What do you think?