Following up on this post about lap dancers, here’s yet another story in The Economist on the mysterious mechanisms of sexual attraction. It seems that there is a part of our DNA that is responsible for building a part of the immune system called the major histocompatability complex (MHC). In mice, MHC also has a role in sexual attractiveness — it changes odors (in the case of mice, the odor of urine) to make some mice more attractive to others as mates. The same turns out to be true for humans: A study ten years ago showed that females recruited to smell t-shirts that had been worn for three days by men preferred the t-shirts from men whose MHC was most different from their own. The theory is that selecting a partner with different MHC will result in offspring having stronger immune systems.
Interestingly, women on birth control pills do not have the same preference; they prefer men whose MHC is most like their own. Because the pill mimics pregnancy, the theory here is that this leads pregnant women to prefer close relatives, which may also be evolutionarily beneficial.
The kicker is that a dating service, ScientificMatch.com, is using this research to help lonely hearts find their perfect MHC match. According to the web site:
The DNA analysis at ScientificMatch helps you find a partner with physical chemistry. When you share the magic of chemistry with someone, you’ll realize some amazing effects—which, admittedly, often sound fantastical. …
When you share chemistry with someone, you significantly increase your chances of realizing these amazing benefits:
1. You’ll love their natural body fragrance–they’ll smell “sexier” than other people.
2. You’ll have a more satisfying sex life.
3. If you’re a woman, you’ll have a higher rate of orgasms.
4. There will be less cheating in your exclusive relationship.
5. As a couple, you’ll be more fertile.
6. Your children will be healthier.
Whoo-eeee! I suspect that there are more things than MHC that control attraction, but I firmly believe that attraction is guided on a fundamental level by chemical and biological elements we aren’t (and can’t be) conscious of.
Ah, the mysteries of love.
Categories: Science