DNA-based Dating

THE RECORD -- Mar 10 -- For Eric Holzle, the  founder of ScientificMatch, the quest for romantic compatibility begins not in the heart but in the cheek. Clients submit a cheek swab which is assessed for genetic compatibility with other clients. This stretch of DNA, known as the major histocompatibility complex (MHC), plays a fundamental role in the immune system. The immune system, in addition to fighting off disease, is the source of our sex appeal. The ScientificMatch membership costs $1,995.

The full article was originally published at The Record, but is no longer available.

Mark Brooks: I tried a 23andme.com DNA test recently. It told me I had a higher than average chance of developing diabetes, and a less than average chance of developing heart disease. It cost $1k. In time we'll see DNA tests enter the mainstream and novelty social networking sites will seek to utilize the 'identity' information that is locked up in our genomes. In 30+ years will dating sites include peoples DNA 'identities' as a standard part of their matchable profiles? Your comments please.

Comments

[Ross Williams]

Sounds like the sort of thing a modern day Final Solution - wow, crazy stuff.

I'm really intrigued by the idea of 23andme.com and am preparing to get a result from that - I think it's got great use to help people care for themselves better.

Using this kind of thing for dating is a bit desperate - nurture will have a far greater effect on personality and compatibility than nature.

This DNA matching service may be suitable for seeing if there's physical chemistry between people, or useful for couples considering children to check for any genetic issues.

But for people to need to do this they've probably done online dating, offline matchmaking and more - one step too far for me but very interesting.

Ross

[Mike]

If we ever figure out what all the genes actually do and the tests become cheap I'm sure genetic information will play a role down the road... I doubt our generation will ever be entirely comfortable with the idea but kids 30 years from now will probably be tested at birth for medical reasons. When they go into the social and dating spheres they'll be more likely to have access to that information.

As far as the scientific match goes, the thing they're testing for has been found to be a component in attraction (when there's dissimilarity in your MHC ) but that's no guarantee of long term stability.

[Michael]

A very slippery slope. Apparently the guys at ScientificMatch never saw the movie Gattaca. Or maybe they did...

http://en.wikipedia.org/wiki/Gattaca

"In a "not too distant" future, where genetic engineering of humans is common and DNA plays the primary role in determining social class..."

[Fernando Ardenghi]

From
http://www.scientificmatch.com/html/the_process_matching_values.php
"the process of finding your best matches
step one - considering your personality: matching values
If DNA matching is the chemistry of our service, then values matching is the heart, where we introduce you to those whom you match at a deep level of your mind.
.........................
When you list these various principals in order of importance to you, it represents your Personal Values Profile.
..........................
One thing you'll love about our values matching process is how fast and easy it is. The simplicity of the theory extends to the ease of the test. In fact, there is no test! Rather than answering hundreds of exam questions, you simply arrange your values in the right order for you. "

From http://www.scientificmatch.com/html/about_more_about_benefits_chemistry.php
"the process of finding your best matches
step two - the process of finding chemistry
For you, finding your chemical matches is the easy part.
..............
Also, we never look at your full DNA profile. We only look at the small fraction that defines your immune system. "

From http://www.scientificmatch.com/html/the_process_personal_preferences.php
"the process of finding your best matches
step three - considering your personal preferences
The personal preferences section allows you to tell us more about who you're looking for. It includes things like age range and distance from where you live.
......"

-- For step 1 and 3

" .. There is no test! Rather than answering hundreds of exam questions, you simply arrange your values in the right order for you." and "tell us more about who you're looking for"
That is only a sophisticated way to search in a database!!!

-- For step 2
As it says "scientific match", it would be great if the founder can explain how exactly the algorithm matches people and which is the ensemble, precision and how results are displayed (without revealing proprietary information) because when it says "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 .... "
http://www.scientificmatch.com/html/about_more_about_benefits_chemistry.php
Unfortunately
* The divorce rate in (United States of) America hovers between 50 and 75% (Kreider and Fields, 2002).
* It seems that what is important in attracting people to one another may not be important in making couples happy (long term relationship).
* Randy Thornhill discovered that women, in an unconscious bid for better genes, will have affairs with men who are more attractive (though perhaps less likely to commit) than their long-term mates.

Kindest Regards,

Fernando Ardenghi.
Buenos Aires.
Argentina.
[email protected]

[James Houran]

Many actual online daters with whom I spoken and who are interested in compatibility testing find this approach "creepy," to say the least.

And in a way, the approach is misleading. Even assuming that it could match two people who would find each other physically attractive -- so what? No one needs DNA testing or any instrument to determine whether there is physical chemistry with another person. Now psychological compatibility is another story. Evaluation of variables like belief systems, expectations, etc. which are the core of long-term compatibility is something that DNA appraoches like this completely miss.

Couples do not stay together because of physical factors -- i.e., passion remains present and steady across the "life" of a relationship. Couples stay together due to cognitive factors. I see services like this playing on the public's thirst for illusions like "soul mates" and "never ending passion." Moreover, sexuality experts like Dr. Yvonne Fulbright will tell you that arousal, sexuality and passion are as much about cognitive factors as they are about "DNA."

But back to the DNA science. There is no peer-reviewed study that validates this method for predicting relationship quality (be it sexual or romantic). That is what's sad here... services using unsubstantiated claims of science to prey on consumers.

Thx,

James Houran, Ph.D.
OnlineDatingMagazine.com

[Eric Holzle, Founder/President, ScientificMatch.com]

I'm astounded at how thoroughly misinformed Dr. Houran is about ScientificMatch, and the science of human attraction. It appears he felt compelled to share his opinion about our service without even visiting our website.

If he had, he never would have written, "There is no peer-reviewed study that validates this method for predicting relationship quality (be it sexual or romantic)." The fact is, we site OVER 40 PEER-REVIEWED SCIENTIFIC STUDIES to support our genetic matchmaking.
By visiting this page, http://www.scientificmatch.com/html/about_more_about_benefits_chemistry.php, he would have seen them. There, we list the six benefits of our genetic matching, and we describe them in detail. We also cite the peer-reviewed references DIRECTLY IN THE TEXT, immediately following each applicable statement. Then, at the bottom of the page, we spell out a full listing of each citation, for easy access for anyone who's interested in further study.

Obviously, Dr. Houran isn't one of those people. He seems much more interested in libeling legitimate services from his perspective of consummate ignorance.

[James Houran]

Dear Eric,

I've previously seen your website and read carefully and with great interest the page to which you refer.

I'm sorry you feel that my comments mischaracterized your company, but no where does that page provide any peer-reviewed, scientific study proving that YOUR particular methods predict relationship quality (stability and satisfaction) in your customers.

Instead, that page simply lists some citations that support the general notion that genetics may play a role in mate selection for some people. That's interesting and provocative reading to be sure, but your list neither references any studies that contradict your claims (to give a balanced view to consumers) nor does your list reference studies that specifically involved your company.

Please share with the industry the 40 plus experiments on your customers proving your matching system works -- and works better than chance or placebo/suggestion effects. I don't see those studies referenced anywhere. Further, that crucial ommission from your website is the main source of my previously posted criticisms and comments.

I'm data-driven, as are all good scientists. With that in mind, I'd be the first to offer congratulations had you published evidence for your particular services. You haven't done so from all accounts, and it's misleading to claim that those studies you cited prove that what you're specifically offering is anything valid or statistically relevant.

As a sign of good faith, my team will be happy to conduct a study co-designed by your firm that independently evaluates the effectiveness of your services. And this would be entirely pro bono. The results -- pro or con -- would then be submitted to a peer-reviewed scientific journal to add to science's knowledge of mate selection.

You see, I'm so interested in learning more that I'm willing to actually conduct a formal study. Are you equally willing to subject your claims and methods to further study? I hope so!

Let's get started right away. You'd be of the only such companies to cooperate with independent auditing of your science. It'd set a great example for other services who fail to substantiate their claims of being "scientific matchmakers."

I look forward to hearing from you.

Thanks,

James Houran, Ph.D.
OnlineDatingMagazine.com

[Eric Holzle, Founder/President, ScientificMatch.com]

Dear Dr. Houran:

Thank you for taking the time to review our website, but your gross misrepresentation of our service suggests that closer scrutiny be exercised.

You wrote, "no where does that page provide any peer-reviewed, scientific study proving that YOUR particular methods predict relationship quality (stability or satisfaction) in your customers."

I couldn't disagree more. In fact, we based our methods exactly on the peer-reviewed studies we cite.

The first of the six benefits we claim is that, "Chances are increased that you'll love the natural body fragrance of your matches." We base this claim on a series of studies that are commonly referred to as the "Sweaty T-Shirt Experiments".

First off, please notice how careful we are NOT to exagerate our claims. We don't say that you WILL love the natural body fragrance of your matches, we say "CHANCES ARE" you will. The genetic science we apply is not absolute, and we don't represent it to be. Which makes it even more offensive when you write that we "prey on consumers". We have the utmost reverence for our customers, and your claim to the contrary is insulting and inaccurate to the extreme.

To continue, in the sweaty t-shirt experiments, the natural body odors of numerous individuals were rated by numerous other individuals. Some individuals were rated as smelling "very sexy" or "very attractive" by specific other people, while others were rated as smelling very unattractive. Many were rated somewhere in between. The majority of the studies showed that the degree of attractiveness was inversely proportional to the similarity of the MHC genes between t-shirt wearer and t-shirt sniffer.

The observed genes in these studies were EXACTLY THE SAME GENES that we use to match our members. In fact, we designed our service to be in exact conformance to these studies. We observe EXACTLY THE SAME GENES.

I could continue to go through all six of our listed benefits in the same manner, but again, I urge you to study our website. It's all spelled out there.

I'll be the first to admit that some of the studies we cite are not based on exactly the same MHC genes that we observe, but those studies are intended to illustrate the overall theory that nature encourages us to breed with--and makes us more attracted to--members of the opposite sex who posses different immune system genes from ourselves. However, the most significant studies we cite are indeed based on EXACTLY THE SAME IMMUNE SYSTEM GENES THAT WE OBSERVE.

Another point you make is that we don't cite any studies that contradict our claims. Can you show me another business that advertises studies that contradict what they do?! Of course not--it's not their place to! But I will tell you this: We don't make a single claim that's based on obscure studies that contradict the overall body of knowledge. Every one of our claims is based on peer-reviewed studies that CONFORM to the overall state of the art and accepted scientific knowledge of the field.

The final point you make is that we haven't produced any peer-reviewed studies ourselves, in-house. You wrote, "I'd be the first to offer congratulations had you published evidence for your particular services." This is the first time I've ever heard someone criticized for using INDEPENDENT STUDIES to support their claims. Now you claim that we prey on consumers, but if WE'D publised the studies we cite, you'd be the first to congratulate us? I'm stupefied by your logic.

[James Houran]

Dear Eric,

There are too many holes in your own logic and comments to review here. Bottom line is that I stand by my assessment of your website.

No where do you reference any studies that support the predictive validity of YOUR precise methods. You even basically admit this yourself. Yes, I would have congratulated you had you actually conducted validity studies on your matchmaking service, but you didn't.

What you've done is cite studies that seem to show that some people are more ATTRACTED to others possibly because of genetic predispositions. That's not the same as relationship quality -- as I've repeatedly pointed out on this thread. Being attracted to someone is not the same as matching people for a lasting relationship. And those studies you cited have substantial shortcomings in the measurement of the psychological variables, so I'm not convinced that the level of attractiveness was indeed as reported.

You claim you "observe" the same immune system genes that most of your cited studies observed. How do consumers know this for sure? Your "word?" Sorry, but I don't inherently trust the opinion of a service that's keen to sell me on the very thing on which it issued an opinion. Instead, I trust scientific studies and audits for quality controls.

All I see on your site are selected studies that would seem to support only your basic rationale to matchmaking, but not necessarily the validity and efficacy of your service per se. In fact, I'd hope your methods wouldn't involve the awkward task of having clients sniff sweaty t-shirts.

That said, it's commendable that at least you're basing your approach on a rationale with tangential scientific merit. Some compatibility services don't even do this. However, if the DNA approach you use is only intended for or valid for matching people based on "physical attraction" then I'd that's not really a big deal. More to the point, the finding would be underwhelming at best from the standpoint of a commercial business model.

People don't need DNA tests (especially paid ones) to tell them with whom they have "chemistry." Past and current human population statistics underscore this nicely. To be sure, that's the one part about relationship development that most people are really good at already -- sensing chemistry and feeling attraction. Romantic compatibility tests if done well offer something above and beyond this. They can be effective in matching people for psychological compatibility, which research shows is the factor that keeps couples bonded and satisfied over the long term.

Let's get back to my offer, which cuts through the "noise" and gets to the heart of the matter (no pun intended). My team will work with your team to conduct a scientific test of your matchmaking methods. Specifically, I propose we'd test to what extent your methods predict relationship quality, not simply the superficial element of "attraction." Let's see if indeed immune systems genes match people that'll have more stable and satisfying relationships than couples matched by chance, a control condition (for suggestion effects) and a typical type of compatibility test.

Let's begin immediately. I'm sure Online Personals Watch and onlinedatingmagazine.com would offer any support in this endeavor possible. Plus, we could improve on previous methodological pitfalls in the studies you did cite, thereby providing a valuable conceptual replication and extension to important literature.

I can only assume you'd be extremely agreeable to this proposal. After all, if you have confidence in the studies and claims you cited, and confidence in the way you've built a service based on them, then the study should clearly come out in strong support of ScientificMatch.com. Excellent PR would no doubt follow for you.

Thanks,

James Houran, Ph.D.
OnlineDatingMagazine.com

[Eric Holzle, Founder/President, ScientificMatch.com]

Dear Dr. Houran:

Your call for a study of our service surprises me. You already came to a conclusion on March 12th, when you proclaimed, "That is what's sad here... services using unsubstantiated claims of science to prey on consumers." Why endure the inconvenience of gathering evidence for your statements, when you've got the gift of making such judgments without basis?

Your blatant disregard for the scientific process is reckless, unethical, and probably illegal in the form of defamatory libel.

I'm sure you'd love to be associated with ScientificMatch, and I don't blame you for trying to embark on a scientific examination with us. I enthusiastically welcome healthy skeptics to engage in scrutiny of our service, but doing so with you would betray my responsibility of maintaining the scientific integrity of our service.

For the sake of your credibility and ours, please retract your defamatory statements about ScientificMatch. The fact that you're not willing to believe that we test the genes that we say we do is no basis to condemn us as predatory.

[James Houran]

Dear Eric,

As a psychologist, I couldn't help but notice the pattern of behavior in your posts. You don't seem to have a good grasp of the material you are citing, you don't seem to understand the nuances of translating experiments to real-world applications and you try to rely on personal attacks rather than address the facts presented.

Let me be more direct in challenging your claims and benefits. It raises serious concerns that you get so emotional and irrational when someone qualified to challenge your "science" raises legitimate questions. Like it or not, this is how science works. Selectively choosing evidence to cite, and not understanding the limitations of that evidence in the first place strongly suggests that you've had no formal scientifc/research training.

I'm a highly published author and a peer reviewer for many journals including British Journal of Psychology, Perceptual and Motor Skills, Personality and Individual Differences, Psychological Reports, North American Journal of Psychology and the Journal of Nervous and Mental Disease. I've collaborated with some of the most respected compatibility researchers in the world, and I'm an active researcher on the psychology of compatibility -- especially computerized matchmaking. I'm quite confident that my credibility and education can stand up to yours.

As an ethical and trained scientist, I'm data driven. That means I'm a healthy skeptic who aims to test claims well before accepting them. Because of this, I've had to let go of notions that were previously assumed to be true. For instance, it was common practice to assume that compatibility was strongly dependent on similarity of individual characteristics (i.e., "birds of a feather flock together").

This principle is still being marketed to consumers (e.g., eHarmony). However, state-of-the-art analytics show the similarity principle to be a gross simplification at best. Therefore, I no longer tout the merits of the similarity principle.

I simply follow where the evidence leads. The problem is I don't see any compelling evidence that your particular approach is meaningful. It MIGHT be an excellent approach for consumers, but that claim needs to be tested. That's what I proposed to do, and that's what you've repeatedly avoided. Your avoidance makes people wonder.

The fact is that your own website and words argue against your positions:

1. My position is that, practically speaking, consumers need not invest in DNA testing to find someone with whom they're physically attracted.

Your position is that DNA testing will facilitate the process of finding someone with whom you'll be physically attracted. I don't agree that the studies you cite definitively support this idea. But, let's say for the sake of argument that they do unequivocally support this notion. My response is "no big deal." Again, people don't really need help in this arena, and one needs to carefully study the effect sizes in the cited studies to determine if the effect sizes have clinical significance in real-world settings rather than mere statistical significance in controlled-study settings. Not to mention close scrutiny about the psychometrics of the rating scales used to assess attractiveness.

2. My position is that none of the studies you cite support the idea that matching on immune system genes will result in relationships of significantly higher quality (defined as relationship stability and relationship satisfaction).

Your position from the above thread is the exact opposite -- you claim there's evidence for this idea. However, your own website information appears to agree with me. This messaging is taken verbatim from your website:

"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 [note: no consensus of experts was offered by ScientificMatch.com] clearly see incredible potential in the power of chemical attraction."

In fact, where are the studies that show your customers who found a "DNA-match" experienced ANY of the numerous physical/sexual benefits that your website cites, as well as confirms that those benefits are clearly attributable to the gene matching?

3. My position is that products advertised as being "scientifically-based" should indeed be substantiated with validity studies. Not just research that supports the general rationale of an approach -- but validity studies that assess the exact service being offered. Your website offers no such studies, even though your recent comment indicates that you agree with me:

"I enthusiastically welcome healthy skeptics to engage in scrutiny of our service."

Since you agree that scrutiny of your service is worthwhile, why didn't you actually test its validity prior to launching your service and taking people's money?

Asking hard questions is not reckless, unethical or libel. Rather, this is the process that science uses to determine fact from fiction and useful versus irrelevant systems. The only conclusions I've formed re: DNA matching are that:

a). It's an intriguing idea that deserves more rigorous study and,
b). Your service thus far has no validity studies to prove that your exact methods yield anything meaningful for consumers.

Rather than being dogmatic, closed-minded conclusions, they represent healthy scientific openness and curiosity. There are no defamatory statements to retract -- only hard questions that I won't let you skirt.

As long as you refuse to answer the important and lingering questions about the meaningfulness of your service, then it's ScientificMatch.com itself that's hurting its self-proclaimed "scientific integrity."

But in the tradition of healthy skepticism and scientific exploration, I'm still willing to conduct PRO BONO a validity study co-designed by your company to be submitted for academic publication. You can even choose the journal. My credentials speak for themselves and Online Personals Watch and Online Dating Magazine can also vouch for my fairness and integrity.

Like me, the industry at large is undoubtedly interested in knowing the truth about the usefulness of DNA matching. You're in the enviable position of being able to help answer this question. Likewise, I stand by my view that services that claim to be scientific should indeed have scientific evidence for their advertised/promised/implied outcomes -- otherwise those companies are preying on consumers with false advertising. How you could possibly disagree is flabbergasting!

Let's stop personal attacks and instead collaborate on learning something new about romantic attraction and relationship formation. Having my well-respected team participate in the study and getting it published would definitely bolster the credibility of your service -- and surely its profitability.

I eagerly await a favorable response,

James Houran, Ph.D.
OnlineDatingMagazine.com

[James Houran]

Dear List,

Here are some legitimate criticisms and questions about ScientificMatch.com (and the entire premise of "DNA dating") from other sources:

http://www.differenceblog.com/search?q=scientificmatch.com

Monday, May 19, 2008
Smelling your way to happiness

The L.A. Times (2008) has a story today that reads like an advertisement for the website ScientificMatch.com. For a one-time fee, members of this site can submit oral DNA swabs for mate-matching on the basis of "major histocompatibility genes" (see major histocompatibility complex: MHC). These genes, thought to be linked to the immune system and reproductive success, have also been linked to whether a particular potential mate smells appealing. However, Thornhill et al (2003) found that MHC influenced men's attraction to women's scent, but not women to men's.

Despite some mixed results, the strongest criticism of the site's business model seems to be that the science is still preliminary. Geneticist J Craig Venter worries that ScientificMatch.com "creates an air of charlatanism that doesn't help the field," Bioethics Institute (2008). The dating site's FAQ warns that the service may not work for women on birth control or those not raised by their birth parents. However, the site welcomes same-sex couples, although little research has been done on the role of histocompatibility in same-sex pairings (exception: Martins et al, 2005).

See also:
http://viv.id.au/blog/?p=1753

This is a must read piece about misinterpretations of the original studies on which ScientificMatch.com is based, as well as ethical questions raised by the whole notion of “DNA dating.”

Finally, see also:

http://news.cnet.com/8301-10784_3-9834683-7.html

for a skeptical reaction from well-known biologist Dean Hamer. This same article sums up many of my arguments well:

"The success or failure of the service can't be measured, however, with only a handful of customers so far. Although [Eric] Holzle doesn't guarantee finding one's true love, he insists that people paired by Scientific Match WILL AT LEAST SMELL APPEALING TO EACH OTHER [emphasis added].”

When a recognized compatibility testing expert, a geneticist and biologist all have questions about the legitimacy of DNA dating as promoted by Scientificmatch.com, then consumers deserve to have a peer-reviewed, predictive validity study conducted to assess the effectiveness/usefulness of the service.

Thanks,

James Houran, Ph.D.
OnlineDatingMagazine.com

[Eric Holzle, Founder/President, ScientificMatch.com]

Here's an exerpt of my reply to Dr. Hamar, the full text of which can be seen on the same CNET page as Dr. Hamar's original comment:

"I respectfully ask what he disagrees with, specifically. We cite over 40 peer-reviewed scientific papers to support our matching process. Does he disagree with any of the articles cited? Did we exaggerate any of their findings? Did we cite obscure sources that contradict the prevailing body of knowledge? We've worked earnestly over the years to ensure that our matching process is based on solid scientific evidence."

Dr. Venter's comment, which originally appeared in the Washington Post, was that ScientificMatch "creates an air of charlatanism". My interpretation is that our service sounds too good to be true. He didn't offer any specifics.

I tried contacting both these gentlemen after their comments were published. Neither was willing to defend their criticism by taking my calls or returning my emails.

I'm also aware of 2003 Thornhill paper, which violates our policy of usage: It doesn't conform to the overall body of knowledge. The majority of peer-reviewed studies on the subject have found that MHC influenced attraction is mutual between men and women.

ScientificMatch is the only dating service in world that matches people with a process that's supported by published, peer-reviewed research. We learn from the investigations of independent scientists, and apply what they've discovered. We're guided by the science, not the other way around.

No other matchmaking service is supported by a single peer-reviewed study--not one. The only peer-reviewed reports related to matchmaking are too general to be useful, concluding things such as the most compatible people are from similar socio-economic backgrounds and share similar levels of education. Some matchmakers operate on the premise that similar personality traits are best, others that opposites attract. It's all speculation, because neither theory is supported by ANY peer-reviewed data.

If the measuring stick of legitimacy is support from peer-reviewed research, then the rest of the industry has a lot of catching up to do to attain the level of ScientificMatch.

[James Houran]

Dear Eric,

I highly recommend that you carefully read a few Psychology 101 textbooks to begin to build a knowledge base in this discipline. I also recommend the general academic books:

Aronson, E., Wilson, T. D., & Akert, R. M. (1994). Social psychology: the heart and the mind. New York: Harper Collins College Publishers.

Wilson, G. D., & McLaughlin, C. (2001). The science of love. London: Fusion Press.

In these basic sources who'll find that indeed there's a rich body of peer-reviewed literature concerning the Similarity hypothesis and Complementarity hypothesis. Let this fact correct your statement:

"It's all speculation, because neither theory is supported by ANY peer-reviewed data."

To begin an education on the data supporting these hypotheses, I recommend a few peer-reviewed articles, for which the citations would be easy to find using any academic search engine:

Dryer, D. C., & Horowitz, L. M. (1997). When do opposites attract? interpersonal complementarity versus similarity. Journal of Personality and Social Psychology, 72, 592-603.

Klohnen, E. C.,& Luo, S. (2003). Interpersonal attraction and personality: what is attrac-tive--self similarity, ideal similarity, complementarity or attachment security? Journal of Personality & Social Psychology, 85, 709-722.

Klohnen, E. C., & Mendelsohn, G. A. (1998). Partner selection for personality character-istics: a couple-centered approach. Personality and Social Psychology Bulletin, 24, 268-278.

Watson, D., Klohnen, E. C., Casillas, A., Nus Simms, E., Haig, J., & Berry, D. S. (2004). Match makers and deal breakers: analyses of assortative mating in newlywed couples. Journal of Personality, 72, 1029-1068.

For a discussion and listing of more primary sources related to the data for similarity and complementarity, I also humbly recommend my own peer-reviewed article:

Houran, J., Lange, R., Rentfrow, P. J., & Bruckner, K. H. (2004). Do online matchmaking tests work? An assessment of preliminary evidence for a publicized ‘predictive model of marital success.’ North American Journal of Psychology, 6, 507-526.

Furthermore, you seem completely ignorant of the history of compatibility testing itself with obviously incorrect statements like:

"ScientificMatch is the only dating service in world that matches people with a process that's supported by published, peer-reviewed research."

"No other matchmaking service is supported by a single peer-reviewed study--not one."

First, as I've shown in previous posts, Scientificmatch.com doesn't have any outcomes data. Instead, it gives consumers citations to support its general rationale to matching, and that general rationale has been debated by academics (scientists don't have the luxury of justifying beliefs with "confirmation biases" -- that is, ignoring contradictory data). Now a rationale needn't be pushed aside because it's controversial, but it's more intellectual honest to admit discrepancies rather than ignore them. Plus, the major study being cited as "proof" doesn't seem to speak to interpersonal attraction at all (much less relationship quality) -- it appears to speak only to how attractive another person's natural odor is compared to that of the smeller's siblings. That alone should've given the investors of Scienticmatch.com pause. Being attracted to a person's smell isn't the same as being attracted to the person. And if interpersonal attraction is observed, it's unfortunately confounded by the artifactual influence of the smell itself (e.g., "Do you really like me or just my scent?!")

Second, as merely one example, I draw your attention to Wilson and Cousins (2003), who published in a peer-review journal their Wilson Relationship Compatibility Indicator (WRCI) test, which yields “compatibility quotients” for couples:

Wilson, G. D., & Cousins, J. M. (2003). Partner similarity and relationship satisfaction: development of a compatibility quotient. Sexual and Relationship Therapy, 18, 161-170.

Dr. Glenn Wilson is often considered to be "Father of Modern Compatibility Testing." He's essentially credited for creating the first compatibility software for commercial applications.

The WRCI is the foundation of the matchmaking service and website Cybersuitors.com. Wilson and Cousins showed that heterosexual couples’ scores on this test show significant and positive correlation (average r = .31, p < .01) with scores on the Marital Adjustment Test. And the effect was shown to be independent of relationship length.

Other examples of data to support specific matchmaking services are easily available to those who know the field.

THE BOTTOM LINE:

Eric, I'm a fair guy but you've tried my patience. I'm an informed party here, so unsubstantiated rhetoric is immediately called out as such.

You seem to have little to no awareness of the vast literature on even the basic theories related romantic compatibility. This makes me question even more now how well your group has understood and implemented the apparent science involved.

Although you boldly claim that "the industry has a lot of catching up to do to attain the level of ScientificMatch," you haven't even shown the effectiveness of your service to be comparable to that of Dr. Glenn Wilson's long-standing and peer-reviewed Compatibility Quotient approach. If you can't show your methods to be at least as good as Wilson's CQ method, then the DNA matching method would seem useless (not to mention a waste of considerable money) to consumers from a practical standpoint.

I publicly and formally challenge Scientificmatch.com to show the public proof that your customers receive ANY benefits implied by your advertising. The industry wants to see actual scientific outcomes evidence attesting to your validity.

If your methods are proven to indeed yield the outcomes you imply to customers, then I'll post a full retraction of my criticisms. I won't post an apology, because to me this isn't a personal quarrel. This is an open-minded scientist trying to vet the accuracy of a claimed scientic process. This is something that should've been done a long time ago as part of your work "earnestly over the years to ensure that [y]our matching process is based on solid scientific evidence."

We'll then publish the study and Scientificmatch will gain more PR and credibility. The side benefit, Eric, is that you'll see me with "egg on my face!"

I can assemble a team of respected compatibility and research experts to oversee the study. That way, it'll be fair and balanced. We can even create and post a video showcasing the study's results and implications on YouTube -- thereby giving you even more powerful PR. I'll also prepare a major article on the findings for OnlineDatingMagazine.com. And all of my team's participation would be PRO BONO.

The hypotheses to be tested are straightforward:

Couples matched by "DNA matching" will score significantly higher than control groups (one paired by traditional methods, one paired by Glenn Wilson's CQ) on measures of physical attractiveness, sexual satisfaction and general relationship satisfaction.

Still hoping for collaboration in the spirit of scientific exploration,

James Houran, Ph.D.
OnlineDatingMagazine.com

[Fernando Ardenghi]

Dr. Houran,
You are definitely the Researcher the Online Dating Industry needs!

Regards,

Fernando Ardenghi.
Buenos Aires.
Argentina.
[email protected]

[James Houran]

Thanks, Fernando!

Like you, I take very seriously my responsibility as a compatibility scientist and industry insider to investigate claims by dating sites that advertise their services as "scientifically based." "Science" can be a powerful selling point to consumers, which means ethically there needs to be substance to such claims.

There's good science out there that can be applied to matchmaking. I give proper credit to those researchers who helped to define this area of academics, and I applaud those dating services who use that science -- be it in matching systems or online content to educate consumers on critical issues with love and attachment.

Cheers,

James Houran, Ph.D.
OnlineDatingMagazine.com

[Eric Holzle, Founder/President, ScientificMatch.com]

Dear Dr. Houran:

Some of the studies you cite I'm familiar with; others I'm not. The ones I have read didn't specify any relationship-enhancing similarity/complimentary personality traits other than very broad generalities, such as the ones I listed previously.

I'm not the only one who seems to have missed the breakthrough to finding the key to relationship satisfaction. This is an excerpt from a blog by Dr. Helen Fisher:

"We tend to be attracted to those of the same ethnic and socio-economic background, as well as those with a similar intelligence, good looks and religious values. We also fall in love with those who supply our needs. And certainly your childhood plays a role. But when scientists administer personality tests to long-married couples, NO patterns of personality similarity or differences emerge."

The emphasis on the word "NO" is hers, not mine. Perhaps she'd enjoy the same educational post that you previously addressed to me.

You can view her original blog entry, here: http://helenfisher.typepad.com/helenfisher/2007/02/lovefrom_from_a.html.

As you can see, the main subject of that entry is MHC matching, which I think is interesting in-and-of itself.

Here's another excerpt from her same blog entry. Keep in mind that I don't know Dr. Fisher, and she has no reason to support me or ScientificMatch. In fact, as a competitor, her incentive is exactly the opposite. As with all the peer-reviewed studies we cite, she's a completely independent source:

"But get this. Scientists have now looked at MHC compatibility among romantic couples and they report that the more genes in this system that a couple share, the more sexually unfaithful the woman is and the more she is attracted to other men..."

That's right--when matched by MHC genes, women cheat less in exclusive relationships.

The peer-reviewed study to which Dr. Fisher refers is from 2006, out of the University of New Mexico, and it's cited on ScientificMatch. In it, they looked at romantic couples, a variety of measures of relationship satisfaction, and their MHC genes. Specifically, they looked at the MHC genes HLA-A, HLA-B, and HLA-DRB. Care to guess which ones we examine at ScientificMatch? That's right--exactly the same genes. Which also happen to be exactly the same genes observed in the sweaty t-shirt experiments.

The same study showed that, when two partners in a romantic relationship don't share similar HLA-A, HLA-B, and HLA-DRB genes--again, exactly the same genes observed by ScientificMatch--they experience higher levels of sexual satisfaction. In fact, women report enjoying significantly higher rates of orgasm.

I realize you'd be happier if these results were published by ScientificMatch, but I'm much more comfortable knowing that they came from a totally independent source. As you said in a previous post, "Sorry, but I don't inherently trust the opinion of a service that's keen to sell me on the very thing on which it issued an opinion." Now you're talking!

So there you go: A peer-reviewed scientific study that shows a higher degree of relationship satisfaction--by several different measures--using EXACTLY THE SAME PROCESS as ScientificMatch. In your forthcoming post, please retract your initial libelous accusation that we use "unsubstantiated claims of science to prey on consumers."

[James Houran]

Dear Eric,

Just when I thought you couldn't amaze me further, you do.

I shouldn't have to say the following, but one opinion on a blog isn't a substitute for the actual peer-reviewed scientific studies. And one study is not scientific consenus. And that ONE study between "relationship-quality" and gene matching you mentioned shows only a correlation (not causation) and the study also has psychometric issues with the measurement of relationship quality. And just how strong was the effect size anyway?!! Statistical significance is not the same as clinical relevance.

You need to carefully read and be able to understand the nuances of these studies in the first place before being able to properly interpret and apply the results. You don't seem to have this expertise.

As for personality similarity versus complementarity -- I never stated that either principle applied to personality traits. In fact, I've strongly argued that similarity in personality triats is not a predictor of relationship quality. The VAST literature on the two theories, however, extends to many individual characteristics and predictable trends do emerge. Those familiar with the literature (or who have taken a Psych 101 course) know this already.

I wouldn't care if the studies you cite were conducted by you. It wouldn't matter. These are correlational (not causal) studies at best, which have notable confounds. Their methodological limitations really cry out for more rigorous study under real-world conditions. Even Dr. Fisher would agree.

So again, you can't skirt the issue of a REAL validation study of your services. So again, you haven't proven that YOUR customers receive ANY of your implied benefits. So again, you're trying to avoid the challenge I put to you that would only bring you added credibility and PR if your claims are valid.

As for the breakthrough in finding relationship satisfaction, Dr. Fisher is well aware of what seems to be a well-tested formula. I know Helen, and we've discussed it before. It's a principle that again is well known to those who know the literature. It's really a cognitive principle that was fleshed out by Dr. John Gottman: the ability to focus on the positives and downplay the negatives in the relationship over the life of the relationship.

This all brings me back to my challenge. Dr. James Houran has publicly called out Scientificmatch.com to put up or shut up!

From what I've seen on your website and your statements on this blog, Scientificmatch.com has no outcomes data validating its methods.

PLEASE prove to the industry and the consumers who spend hard-earned money on your services that YOUR customers receive ANY of the advertised and implied benefits to a degree significantly greater than chance and control groups.

Quit referencing studies of which you've no real understanding of their meaning. It has been terribly embarassing to watch you do this repreatedly.

Many experts, like me, who know what they're talking about have publicly called into serious question your approach for extremely good reasons summarized in my previous posts. Furthermore, you've not contradicted ANY of my arguments yet. In fact, you go to great pains to avoid addressing the hard questions I pose.

By refusing my challenge and offer to properly test the benefits received by your customers shows YOU'RE SCARED and INTIMIDATED of what a rigorous validity study by experts in the field will reveal.

I'm dead serious in my research offer. You've seen the simple, straightforward hypotheses. You've no grasp of compatibility literature and the genetic studies you cite, so debating these with me is worthless for your case.

Let's cut to the chase here. Is your service meaningful or just snake oil? It's a mystery to many experts. The jury is still out, so to speak. There's no definitive view in the scientific community. You can help to resolve this.

That said, are you ethical, scientific and open-minded enough to participate in a real validation study of your services or are you not?

Continuing to hope for collaboration in the spirit of scientific exploration,

James Houran, Ph.D.
OnlineDatingMagazine.com

[James Houran]

Dear Eric,

One more thing. The University of New Mexico study that you rely on to help “prove” your claims only examined MHC sharing in relation to sexual attraction. And there are serious methodological pitfalls in the self-report assessments used. In other words, studies using the psychometrics they did aren't convincing to tests and measurement experts.

Furthermore, and this is the nail in the coffin, the authors of the University of New Mexico study wrote that, “MHC SHARING DOES NOT BROADLY PREDICT RELATIONSHIP SATISFACTION.”

Online daters don't need an expensive test and wait days or weeks to discover who they MIGHT find sexually attractive. A trip to a large shopping center will likely worker better, faster and definitely cheaper.

And the DNA dating approach seems to offer nothing meaningful for relationship quality. You haven't even shown an effect size equal to Dr. Glenn Wilson's peer-reviewed, validated approach.

Eric, why are you blind (or closed-minded) to what everyone else seems to know at this point? Even your own wording on Scienticmatch.com admits you system can’t match for love or emotional attachment.

Ignorance is one thing, but now that you’ve been educated and know the true weight of the evidence, there are no reasonable excuses. It’s time to revise your site’s advertised and implied claims. Or, you can be responsible and test whether your customers receive any of the claimed benefits.

Thanks,

James Houran, Ph.D.
OnlineDatingMagazine.com

[dater not a hater]

I've been reading this thread for its entertainment value. I have to say that the DNA dating dude is losing this debate.

Eric, you won't win against Dr. Houran with the same arguments that now are so full of holes it only hurts your company to continue speaking.

I think it's cool that Dr. Houran offered to help run a test of the service. I think his offer is sincere. You have nothing to lose if what you claim is true about matching people on genetics.

Stop all this bickering and prove this stuff works on real customers. As an online dater who has tried many websites, this is the only way I personally would be convinced it works as advertised.

Terry

[Jodie]

Dear Mr. Houran:I've been reading this dialog between and Mr. Holzle. I have a question for you Mr. Houran you say you are a scientist, when it appears you are a Psychiatrist, so the question is what scientific background or degree to you hold that places you above Mr. Holze? What makes you more qualified to place such an opinion on someone or to "publicly" challenge them? My intuition tells me that since you have "publicly" challenged Scientific Match to "put up or shut up" and the arrogance you display within your postings I don't think I would trust your results. Through your posts you show signs of a person who would never allow anyone to "throw egg in your face". You live in different states how could ANYONE be sure you wouldn't skew the results, because in my opinion this looks more like a vendetta against Mr. Holzle because he continues to challenge his site. I personally think science is too "Cold" and it takes the fun, romance and passion out of the wholething. Studies are just that studies. It's 1 persons opinion on a select amount of people and then generalized as to the entire human race, which I disagree with I need more facts then that. You cannot predict "chemistry" It's different for everyone. Why don't you take science out and Have Fun... Mr. Houran are you in a successful long term relationship filled with passion? If not maybe you should use Mr. Holzle's service. If you're single then perhaps we should question that then and the advice you give to single people. Unless you are in a longterm loving and passionate relationship how can you give insight on what makes for a good relationship? Why because you're "book" smart?? Unless you have had a long relationship you have no clue what goes on over time. It's the overall compatibility and mutual core values and beliefs that hold a relationship together, and the sex plays a very important role but as we age the values an beliefs hold a higher priority than sex. Sorry boys just ask the woman.

[James Houran]

Dear "Jodie,"

I'm a clinical psychologist, not a psychiatrist (although psychiatrists are human beings too). However, a psychiatrist well trained in social psychology would be a valuable asset to the field since that person would have both psychological and medical/physiological training.

As for me being qualified to challenge the claims of Scientificmatch.com, my sample of credentials above more than makes me able bodied. In fact, several academic journals routinely ask me to review scientific studies on compatibility and attraction.

Plus, as a respected, well-published researcher on interpersonal compatibility and compatibility testing and as an established online dating industry insider, I don't skew results. I've no personal or vested interest in the outcome of a real validitation test of Scientificmatch.com other than to learn the truth about the real-world effects of DNA dating. Other notable scientists (biologists and geneticists) have also publicly challenged the implied claims of DNA dating (again, see above). Jodie, as you can see, I'm not alone in my healthy skepticism.

For these reasons, I proposed a study that would involve a team of additional experts in compatibility sciences and tests and measurements. This keeps both me and Eric in check, so to speak.

Jodie, please take time to read the books I previously recommended above. While you're at it, please re-read carefully all of the questions and resources I openly provided. They're great education about what science does know about love and attachment - and there's a good degree of it that is predictable and measurable. Social psychologists have known this for decades.

My postings were not written out of arrogance. Arrogance is Eric making bold claims and statements that are demonstrably incorrect and obviously incorrect to anyone who knows this field and industry. My postings may come across arrogant to you because I know the compatibility literature and speak to it confidently. I also don't let people skirt hard questions with a song and dance routine.

The only vendetta I have is against companies that use unsubstantiated claims and abusing the term "scientific" to sell consumers on services. Jodie, certainly you would agree that such behavior amounts to false advertising and is unethical and perhaps illegal.

Professional psychological associations are fed up as well, as many editorials and Letters to the Editors of academic periodicals over the years can attest.
Indeed, it's time for Scientificmatch.com to put up or shut up. By put up, I mean participate in a real scientific investigation of their services. It would be a study for academic publication, so the research design and the ethics surrounding the study would have to be exemplary -- again, fudging data is neither necessary nor wanted.

Until the industry and scientific cmmunity is presented with a real-world outcomes study that determines to what extent customers of Scientificmatch.com obtain ANY of the implied benefits, I suggest the company limit its services to selling shirts that read:

"I paid for Scientificmatch.com, but all I got was this sweaty, good-smelling t-shirt."

Thanks,

James Houran, Ph.D.
OnlineDatingMagazine.com

[Jodie]

Mr Houran Thank you for your reply. However I respectfully ask that you do not treat me as if I am not aware of the subject at hand.

Believe me the last thing I want is to get in the middle of this. I have done quite a bit of research on this subject and I have my own personal opinion which I will keep from this forum because as in any situation people do have a differance of opinion.

I will however look into the "recommended" reading you have kindly presented.

However I do find your last comment to be rather rude and insulting to Scientific Match and in my opinion that was uncalled for, as it was not fair to Mr. Holzle and his company.

Mr Houran as I'm sure you are well aware we gain greater respect from people when can act in kindness and respect reguardless of our own "personal opinion" and that is in any given situation.

Thank you for your time.
Jodie

[Eric Holzle, Founder/President, ScientificMatch.com]

So let's review:

1. ScientificMatch preys on its customers.

2. Nobody at ScientificMatch has the ability to read a scientific report. If they did, they'd realize that the 40+ peer-reviewed articles they cite to support their claims are useless. While the citations may insinuate subtle trends under controlled laboratory conditions, they have absolutely no relevance to the real world. (The authors of those studies will surely be disappointed to learn of their inconsequence.)

3. Even if the 40+ peer-reviewed studies do apply to the real world, it doesn't matter because they're irrelevant in the context of a dating service. Why bother screening out the people you lack genetic compatibility with online, when it's so much easier to go down to the mall and sniff out potential dates there?

4. If only we'd recruit Dr. Houran to join ScientificMatch in our own study, we'd achieve great credibility, fame and fortune.

Here's what I think: Dr. Houran recognizes that ScientificMatch is onto something big. Really big. Something so revolutionary that it holds the potential to change the dating industry--and human relationships--forever. Perhaps he wishes that he came up with the idea himself, and he's eager to participate however he can.

Unfortunately Dr. Houran, you're not qualified. One of the most important characteristics of a well designed study--and of the participating scientists--is objectivity. It's the reason we prefer to cite independent articles to support the claims of ScientificMatch, and it's a trait that you're sorely lacking. This first became apparent when you initiated this discussion by describing us as predatory. It was further illustrated when you became emotional as the discussion progressed, (or in your words, trying your patience,) and it was confirmed when you admitted that you'd have egg on your face if the results came out one way or another. You've clearly got a stake in the outcome, which again, violates the first rule of a well designed study. Being skeptical is fine--even desirable--but hostility is not.

Rest assured that as we grow our real-world database, we'll work in earnest to further verify our original claims and to adapt our service as the science evolves. In the mean time, we're very secure in standing on the findings of independent research.

I personally vow that ScientificMatch will bend over backwards to satisfy any customers who become disgruntled in the process. We do not, under any circumstances, prey on our customers.

I realize this won't satisfy you. I'm sure you'll continue to disparage ScientificMatch in your attempt to extort us into recruiting you.

I don't see much purpose in continuing this discussion. We'll just have to agree to disagree.

I'll even end things on a high note, by applauding you for replying to my messages. As you pointed out, some others have demeaned our service in the past. I always try to respond when this comes to my attention, because I believe so strongly in the integrity of ScientificMatch. Some of these "experts" have retracted their remarks, others have not. But most won't even engage, which to me seems cowardly. I may not agree with your opinions, but at least you're willing to expound upon them. For that Dr. Houran, I thank you.

[James Houran]

Dear Eric

All you do is constantly skirt the issue of validity, which probably doesn't surprise followers of this thread but which is disappointing nonetheless.

It'd be very interesting to know what experts (names, affiliations) have retracted their criticisms of your service, because I've not come across a single example yet.

That aside, emotional, unobjective (and downright ignorant) rhetoric from someone with a vested interest in the financial success of Scientificmatch.com is no substitute for scientific evidence.

Please stop the hostility and side-stepping of the issue at hand. Instead, please accept my team's repeated and generous PRO BONO OFFER of an actual validity test of your advertised claims.

I've patientily held out hope you'd be objective, but it seems increasingly clear now that you're passionately committed to avoiding a validity test and likely won't ever participate in a well-designed outcomes study by knowledgeable and well-respected compatibility scientists.

This speaks volumes -- as have all of your arguments, views and behavior here. Even without participating in a real outcomes study of your advertised claims, you've repeatedly and strongly indicated to the industry and online dating consumers that there's no meaningful basis for your services.

Thank you for the extremely informative dialogue and for helping consumers to understand the validity of your service better.

James Houran, Ph.D.
OnlineDatingMagazine.com

[Susie]

Hey I thought this was interesting. Why would a man who has his own dating website be on other dating sites?

I was crusing around some dating websites and I thought the guy looked familar. It's Eric Holzle from Scientificmatch.com and he's on more than 1 site. I can't say I would want to date someone who uses other dating services to seek woman. No wonder why he's a "Life long Batchlor" Wouldn't be surprised if he tries to date someome off his own site.

Just kind of Creepy