DNA Matching & the Magic of Chemistry

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. We’ve identified six specific benefits of chemistry, which we’ll describe in detail—complete with sources cited. These sources (except for one, the New York Times,) all meet the gold standard of researched information: They’re all peer-reviewed articles published in renowned, scientific journals. Of course, the results represent averages across populations; individual experiences may vary. The benefits shown are in comparison to couples who are inappropriately matched according to our DNA-matching process, all other things being equal.

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.

First, we explain what physical chemistry actually is. Then, each of the six benefits listed above is described in detail.

To learn more about chemistry, we invite you to visit some of our other pages, too:

The matching process— how ScientificMatch delivers the magic of chemistry to you.

How our genetic matching works with people seeking same-sex relationships.

Why genetic matching doesn’t work for women on birth control pills.

Why it won’t work if you weren’t raised by your natural parents very early in life.

The controversy surrounding “human pheromones.”

Physical Chemistry Defined

Physical chemistry is based on the immune system. When we analyze your DNA, we look exclusively at your immune system genes. So, quite literally, when we say that two people have “chemistry”, we’re saying that their immune system genes are perfectly matched with each other.

By perfectly matched, we mean different. After we analyze your DNA, we match you with other people who have different immune system genes from yourself.

The theory is that nature wants us to breed with other people who have different immune systems because it creates babies with a wider variety of immune system genes, and therefore, more robust immune systems—in other words, healthier babies. [Doherty & Zinkernagel, 1975; Dyall et al, 2000; Mitton 1993 & 1997; Penn et al, 2002] It also discourages inbreeding and the associated health consequences [Dobzhansky, 1937; Potts et al, 1994; Apanius et al, 1997; Grob et al, 1998; Penn and Potts, 1999; Penn, 2002], and it enables us as a species to adapt to changing diseases and disease environments. [Bodmer, 1972; Burnet, 1973; Wakeland et al, 1990]

Since nature’s goal is to perpetuate the species, it encourages us to mate with others who have immune systems different from our own.

For example, you’ve probably noticed that you’re not sexually attracted to your brother, sister, mother, or father. That’s because they’re all part of your immediate gene pool, and you all probably have very similar immune systems. Nature doesn’t want you to mate with them, because the health of your baby, and the longevity of our species, would suffer.

You may have experienced the power of chemistry in another way: Perhaps you know someone who looks just like “your type”, but somehow you just don’t feel that “sexual spark” when you’re together. They seem more like a brother or sister than a potential lover. It could be that you have too much in common—namely, your immune system genes.

Conversely, maybe you’ve found yourself talking to someone who you distinctly did NOT consider to be your type, and yet with whom you distinctly DID feel a sexual spark. Again, your immune system genes could be at the source.

More about the Benefits of Chemistry

When you share chemistry with someone, the benefits are truly amazing. We believe it could literally mean the difference between a bad relationship and one of bliss. Here, we give a more detailed description of the six benefits of chemistry.

Again, these claims represent aggregate results observed over sufficiently large populations, and individual experiences will vary. But overall, the power of chemistry is pronounced, dramatic, and well documented.

1. Chances are, you’ll love the natural body fragrance of your partner--they’ll smell sexier than other people:

Nature attracts us to our genetic matches with our noses. The fact is, we love how other people smell when their immune systems are different from ours—they smell sexier.

This was first shown in the renowned 1995 study lead by Claus Wedekind, [Wedekind et al, 1995] often referred to as the “Sweaty T-Shirt Experiment.” In it, he had women sniff t-shirts that had recently been worn by men—without any artificial or external colognes or scents. They found that the “sexiness” of a man, or rather of the smell of his unwashed t-shirt, is directly related to how different his immune system is from the woman judging the sexiness. If their immune systems were very different, the women rated the men’s t-shirts as very sexy smelling. Women sniffing the shirts of men who had very similar immune systems to themselves rated those sweaty t-shirts as very “unpleasant.”

Subsequent studies have confirmed similar effects on both men and women. [Wedekind and Furi, 1997; Thornhill et al, 2003; Santos et al, 2005] The majority of the data confirms that we love the smell of the opposite sex when their immune systems are very different from our own.

You may have experienced the power of natural body aroma first-hand. Perhaps you’ve encountered someone who’d just finished exercising or working out, and their body odor reminded you of dirty old gym socks. The first thing you may have done was run away, send them to the showers, or pass out!

Yet, you may know someone else who, when they’re all hot and sweaty, you CAN’T stay away from! Their perspiring body is the most sensual smell you can imagine.

The difference probably lies in your immune system genes.

We’re not encouraging people not to bathe—old stale sweat doesn’t smell good to anyone! But the fact is, we love the fresh, natural body fragrances of other people when their immune systems are very different from our own.

The significance of the sweaty t-shirt experiment was recognized by Dr. Helen Fisher, a research professor at Rutgers University and one of the foremost experts on the subject of desire. She recently spoke with the New York Times [Corcoran, 2007] about it:

“The sweaty t-shirt experiment is, I think, one of the most important, modern, scientific studies. What they did is they gave a group of women a lot of t-shirts to smell; and the women ended up being more attracted—physically attracted—and perhaps even emotionally attracted—to those t-shirts of men who had a different immune system.”

Dr. Fisher concluded her answer with an amazing prediction: “And so the sweaty t-shirt, I think, is the first of many experiments that will end up discovering who falls in love with whom.”

Just to be clear, we don't know of any scientific evidence suggesting that our technology will predict who you'll fall in love with or even be emotionally attracted to. But the experts clearly see incredible potential in the power of chemical attraction.

2. You’ll probably have a more satisfying sex life:

In a recent study out of the University of New Mexico [Garver-Apgar et al, 2006], it was shown that both men and women in exclusive relationships enjoy a much more satisfying sex life when their immune systems are different from their partners’.

The study surveyed a population of men and women about characteristics of the “exclusive” or committed relationships they were then currently in. It also compared their immune system genes to their partners’, to see if there was any correlation. There was.

Both men and women enjoy more satisfying sex lives when they’re a good genetic match with each other, though each sex experiences that satisfaction in different ways.

Women with very different immune system genes from their partner reported being more enthusiastic about sex with their men—and more sexually aroused by them. Those women fantasized about their spouses more often. They desired sex with their spouses more often and turned down their partners’ sexual invitations less often.

Men’s sexual satisfaction is also heightened with partners whose immune systems are very different from their own. Consistent with what the women reported, men said their partners were more sexually turned on by them, and that their female partners were more enthusiastic about sex with them. They reported that their spouses turned them down for sex less often, and wanted to have sex more often. Men also reported that their female partners were more sexually adventurous, and that their spouses tried harder to please them sexually. Overall, the men were much more satisfied with their sex lives when their DNA was a good match with their spouse.

The bottom line is that, if you have chemistry with your partner, chances are you've got a great sex life!

3. If you’re a woman, chances are you’ll have a higher rate of orgasms:

As an extension of the previous benefit, women in the same study from the University of New Mexico [Garver-Apgar et al, 2006] were shown to have a higher rate of orgasms with their genetically compatible mates.

This might seem surprising at first blush, but it’s very consistent with the overall theory that nature wants us to breed with those who have different immune systems from ourselves. That’s because the female orgasm is a mechanism that increases a woman’s chances of getting pregnant during intercourse. So, by increasing the rate of women’s orgasms with their genetically matched men, it could be another way that nature encourages healthy offspring.

4. There’s a lower chance of cheating in your exclusive relationships when your DNA is matched properly:

Also from the University of New Mexico study, [Garver-Apgar, 2006] it's shown, for the first time, that immune system chemistry affects human psychological behavior as well as physical phenomena, like sexual attraction and health of the offspring. It shows that a woman’s chances of cheating are determined very strongly by the degree to which her immune system genes match those of her man. If all her immune system genes are the same as his, she’ll very likely cheat. If half her genes match his, she has about a 50% chance of cheating. And if none of her immune system genes match her partner’s, there’s very little chance she’ll be untrue.

The significance is incredible. No other study has ever revealed, by scientific standards, any other important, reliable predictor, (other than very broad measures, such as similar socio-economic and educational backgrounds,) of long term relationship behavior and compatibility.

Although significant, the results weren’t completely unexpected, as other studies have shown similar behavior in animals. [Blomqvist et al, 2002; Freeman-Gallant et al, 2003, Schwensow et al, 2007] These studies examined the mating patterns of animals that typically stay with their partners for life. But, if two partners have similar immune system genes to each other, the female will often stray from her lifelong partner to breed with others.

Unfortunately, similarity of immune systems has almost no effect on men’s cheating. It seems that men are wired to cheat, or not to cheat, regardless of chemistry. [Garver-Apgar, 2006]

Of course, both spouses benefit from the woman’s fidelity with her genetically matched man—but for different reasons. The man benefits because the woman in his life probably doesn’t cheat; and the woman benefits, because she probably doesn’t want to.

5. As a couple, you're probably more fertile.

In another group of amazing studies, [Lauritsen, 1976; Komlos, 1977; Gerencer, 1978; Schacter, 1979; & Beer, 1981] it was shown that a couple’s fertility is correlated to the degree to which they share chemistry. All these studies show that if a heterosexual human couple shares a high number of immune system genes between themselves, their chances of experiencing spontaneous, unprovoked abortion increases significantly.

To be clear, they don’t show a correlation between chemistry and the ability to get pregnant. That wasn’t investigated in these studies, so they don’t disprove the correlation, either. But they all clearly show that once a couple does become pregnant, their chances of reaching full-term and delivering a baby increase when the immune system genes of the couple are different from each other.

The bottom line: If you want to have children, you have a better chance of doing so when you have chemistry with your partner.

6. Your children have a better chance of being healthy.

This is one of the main reasons nature designed us to be attracted to others with different immune systems in the first place: to produce healthier children—and, to avoid having unhealthy ones.

To match members of ScientificMatch, we perform DNA analysis to look at the immune system genes on the section of the DNA known as the major histocompatibility complex, or MHC. The MHC genes ultimately determine our bodies’ response to invading parasites and pathogens. [Klein, 1986; Kuby, 1997; Janeway et al, 2001] There’s a wide variety of MHC genes, and nature wants us to breed with other people who have different types of MHC genes from ourselves.

To understand why, it’s important to know that our MHC genes are largely co-dominant—that is, the traits they express are defined equally by our mother and father. That’s different, of course, from some other traits, such as eye color, which is typically defined by one parent or the other. But our immune systems are defined equally by each parent.

So, if a mother and father have very different MHC genes from each other, their babies will have a wider variety of MHC genes themselves. [Mitton, 1993; Waser, 1993] That means more robust immune systems that are better equipped to defend against more parasites and diseases.

Indeed, it’s been shown that individuals with a wider variety of MHC genes will “more likely be healthy.” [Potts and Wakeland, 1990; Apanius et al, 1997; McClelland et al, 2003] Another report [Penn et al, 2002] shows that mice with a wide variety of immune system genes are more resistant to disease, and they’re more fit. There’s been more in-depth research showing that genetic diversity is beneficial for specific illnesses such as hepatitis, [Thursz et al, 1997] , human T-lymphotropic virus—a precursor to lymphoma and leukemia, [Jeffery et al, 2000], malaria, [Bhatia & Crane, 1989] and even HIV—a precursor to AIDS. [Carrington et al, 1999] One study [Schacter, 1979] shows that babies born with a wide variety of immune system genes are less likely to have spina bifida and other neural tube defects.

Another principal theory is that nature encourages mating among those with different MHC genes to avoid inbreeding.[Pusey & Wolf, 1996; Apanius et al, 1997; Grob et al, 1998; Penn & Potts, 1999; Penn, 2002] Inbreeding happens when two parents come from the same gene pool, often resulting in any of the following traits in the children: Reduced growth rate and lower weight and height throughout adulthood; higher infant mortality; physical asymmetry, (which correlates to un-attractiveness [Rhodes et al, 1998; Perrett et al, 1999; Little et al, 2001]); reduced fertility; and genetic disorders. Basically, inbreeding creates sickly, and sickly looking, babies.

By making those with similar immune systems unattractive to us, nature discourages us from inbreeding. [Brown and Eklund, 1994; Potts et al, 1994]

Of course, you can still have healthy children with people you meet elsewhere. But nowhere else will your matches be screened to increase the possibility of healthy children, using immune system DNA analysis.

Conclusion:

It’s understood that the six benefits listed above seem preposterous at first blush. Increased chances of a sexy smelling partner, a more satisfying sex life, less cheating in your relationship, and healthier children—how could a dating service offer any of these?

The fact is, the technology we use at ScientificMatch is the only matching process that’s supported by scientific evidence. And not just some scientific evidence—a wide abundance of it.

That’s in sharp contrast to other dating services or compatibility tests you’ve heard of or seen on TV commercials. Not one of them is supported by a single independent scientific study that shows its matchmaking methodology works.

Every one of the six benefits listed above is backed by peer-reviewed, published scientific studies—solid support of our matching process, and the power of chemistry.

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