by Lone Frank
Still, it’s not yet time to forget about the “old” genetics. After all, we know that particular gene variants do have an effect, both physically and psychologically. Should scientists be looking at genetics and epigenetics together, to find out how the two interact? I permit myself to refer to another well-known epigeneticist, Andrew Feinberg of Johns Hopkins University. He has been airing the idea that we might be walking around with gene variants that make it more or less difficult to make certain epigenetic changes.
“Naturally,” says Szyf, once again sighing audibly. “I know of research that is right now looking at psychiatric diseases in identical twins and comparing their respective gene variants and the epigenetic patterns each of them has. But you have to understand the field is young. We are at the beginning of something very big, and we don’t yet know how big it is.”
Actually, I suggest, the really big thing is the discovery of how incredibly dynamic the genome is. This makes me think of an oft-cited quote from 1989, when James Watson, in his usual cocksure way, said to Time magazine: “We used to think our fate was in the stars. Now we know, in large measure, our fate is in our genes.” Some twenty years later, that sounds like a foolhardy and hopeless simplification. Now, we know that genes are not fate, in the sense that our DNA sequence determines the life we get.
“Of course, our fate is partially in our genes, because they lay the foundation for what can happen,” Szyf says. “But there is at least as much fate in the way we interact with each other. We have a very significant influence on how the genes we inherit actually work through the way we interact with the world around us. How significant … research must show.”
Szyf has several appointments on his calendar, and I can almost sense the poor people standing in line, waiting for me to get off the phone.
“What we’re working on now – depending on how much they invest, of course – will shake up the way people think about biological inheritance.” We’re moving away from the idea that the foundation of our life is something quite static to the view that it is something very dynamic and malleable. This is a recognition that will spread throughout the culture, and the interesting thing will be to see how it has an effect on the ways we view and use genetic information in the future. That’s something to think about.”
8
Looking for the new biological man
Finding that “special someone” doesn’t happen in a test tube – it’s a process … Current scientific knowledge can only take us so far – the rest is up to you.
SCIENTIFICMATCH.COM
There’s a pair of white cotton panties in my underwear drawer that I’ve never worn and never will. It’s not because they’re a little too big for my taste, but because across their front and the back is printed a long, slightly blurred sequence of letters – A, G, C, T. It’s hard to decipher and looks more than anything else like the imprint from a wet newspaper.
But actually it’s art. I received these panties from Joe Davis, who, from an office tucked in a corner of the Massachusetts Institute of Technology, concocts art installations involving biological materials such as Petri dishes of genetically manipulated bacteria. Davis hand-printed the panties at home in his kitchen, and the sequence comes from one of his own genes. Not any old gene but one of the so-called human leukocyte antigen, or HLA, genes, which reside on chromosome 6. There is a group of HLA genes, which code for a protein that bristles on the surface of white blood cells, where they play a crucial role in stimulating the reaction of the immune system to infections.
“You have to see this as a commentary on the future and the whole genetic project,” Davis explained when he handed me a size medium. Fair enough. But why panties exactly, and why an HLA sequence?
The project harks back to a famous experiment from 1995, in which a group of women turned out to be attracted to the body odor of men on the basis of their HLA genes. The man behind the experiment was a young PhD student, Claus Wedekind, who as a zoologist was well-versed in the world of animals. He noticed that many species – including mice – prefer a partner with certain genetic characteristics: they sniff their way to the set of HLA genes that is the most different from their own. This appeared to have nothing to do with finding the ideal mouse mate – a supermouse for all seasons – but with the fact that, for every given mouse, some partners complement its particular genes better than others.
When Wedekind explored the idea further, he realized that, basically, the animals were optimizing the fitness of their offspring. Mates with a big difference in HLA provide the offspring that come out of their union with the greatest possible variation in their HLA genes. This, in turn, bestows the next generation with the most flexible immune response.
And if mice are so ‘rational’ in their mating preferences, Wedekind reasoned, why not human beings?
He persuaded forty-nine women to stick their noses into a pile of T-shirts from various men – unknown to the women – who had slept in the garment for two nights in a row without using any form of deodorant or other artificial mediation. In other words, pure, unadulterated body odor. Forty-four men participated in the experiment, and their T-shirts were distributed at random, so every woman gave an opinion on six. The women then described how pleasant or unpleasant the odor of these men was in relation to each other and ranked them by personal preference.
Both the men and the women had been gene-tested for three specific HLA genes – A, B, and C – each of which exists in a number of variants. It turned out that the women did not have the same preferences but clearly favored the odor of men whose HLA type was different to their own. The more difference, the more pleasant the smell, the researchers found. At the same time, the preferred smell was consistently the one the women described as being closest to the smell of their present or past partners. The results were so clear that Wedekind concluded: “Our finding shows that some genetically-determined odor components can be important in mate choice.”
The findings also showed that birth control pills disturb this scent-guided choice of partner. If the women were on birth control pills, which physiologically imitate a pregnancy, their preferences turned upside down. Then, they preferred men whose HLA type was close to their own.
News of the musty T-shirt experiment traveled the world, providing not only headlines but dubious commentary. Could it really be the case that we human beings, with our highly developed culture and refined ways of life, still have such primitive instincts? We just don’t go around sniffing each other – we make social demands of our mates; about appearance, educational attainment, job status, and political views.
Yet a mini-industry of gene research was born. Subsequent experiments from Wedekind and many others have substantiated the fact that odor preference exists and that it applies to both women and men. Field studies indicate that the preference means something in practice. In the United States, Carole Ober of the University of Chicago visited a group of Hutterites, an Anabaptist religious sect known not to use contraception on principle, who agreed to let its married couples be gene-tested. Ober’s study of HLA genes found that, to some degree, the Hutterites married following the same rule as mice – the difference between HLA genes in husbands and wives were greater than what would have been expected if the choice of partners were random. Later, a French-British-Chinese team found a correspondence among “regular” white Americans and gave their support to “… the hypothesis that these genes influence mate choice in some human populations.”
Today, you can subscribe to dating services based on your HLA genes. First off the mark was Eric Holzle, an out-of-work engineer from Boston, who established a dating agency, ScientificMatch. com. His entrepreneurial brainstorm is that users will buy a test for a number of HLA genes, which Holzle then uses to suggest possible partners who might be a good genetic match. More recently, a quasi-competitor, the Swiss company GenePartner, has entered the market, though it does not directly put people together and instead limits its work to testing interested peop
le. As usual, it’s quite easy – you get a couple of cotton buds, scrape the inside of your cheek and that of the other party or parties you’d like to have checked, and post them to the company. Later, you receive access to a closed account on the company’s website, where you can read at your leisure about how well you supposedly fit together, genetically.
“THIS ALL SOUNDS like some kind of animal attraction,” says my colleague J, when he hears about GenePartner, and he clearly finds the thought appealing. So appealing, in fact, that he thinks we should both get a test as soon as possible. This does not come from nowhere. For a couple of years, he’s been energetically advocating that we produce a baby together. It’s not that we should live together or have anything to do with each other in the traditional way – we are both involved with other people – but since his girlfriend can’t have children, he thinks the arrangement makes sense. Particularly from a genetic point of view.
“We’re both good-looking people, right?” he says, referring mainly to himself. When I shrug at it, he argues further that we complement each other well: “You’re gifted in the rational direction, while I’m an excellent example of the artistic, aesthetic type.” An ideal combination, in other words. When I’m not convinced, he moves on to the purely physiological advantages.
“My grandmother lived to be over a hundred, and she was fit as a fiddle right up to the end.” And then the trump card: “My liver and pancreas are in top form!” Which undeniably says something about a robust physique, when you consider J’s consumption of wine. Now, he’s trying a scientific argument as a last resort to persuade me: “We can have an HLA test done, which can show whether we should propagate before it’s too late for me.”
I consent in principle but throw J out of my office so I can call Claus Wedekind. He is no longer a student but a professor at the University of Lausanne, and when he hears of my errand, he releases a heavy sigh.
“I guess I’ll have to get used to the fact that I’ll never be rid of that old study,” he says, explaining that he no longer works with human beings as a model system; he’s far more interested in fish. But every week, at least two journalists from somewhere in the world phone him to take a position on T-shirt odors and attraction. This conspicuously polite and soft-spoken man admits that he is a little tired of it. “I refuse to appear on TV; it simply takes too much time. But I’m happy to answer questions over the phone.”
I want to know what Wedekind thinks about the research field he helped launch, which – in its limited way – has been commercialized and marketed. Is there even enough data to put a product up for sale? Again, he sighs.
“I believe there must be agreement that there are preferences with respect to body odor that are connected to HLA genes. I also believe that there are preferences with respect to human mating. That can be deduced from my own study, and it has been seen in similar studies repeated in other populations.”
That is, there are studies on white Americans. But one of them, released in 2008, found no HLA preferences when it investigated couples of the Yoruba people of Nigeria. And in two other studies conducted in 2000, that tested the HLA genes of three hundred Japanese couples, the degree of difference between HLA genes in spouses appears to correspond to the population generally.
“The fact that some studies have not found any preferences doesn’t speak against the whole idea,” Wedekind insists. He mentions that he is inclined toward the hypothesis that the preference for a mate with different HLA genes developed to prevent inbreeding in the small groups in which Homo sapiens originally developed and lived.
“We don’t know how important it is and how much HLA genes mean for people in relation to other factors. It may also easily be the case that they mean more for some men and women than for others – that there is variation. But if it proves to be something you can use advantageously for dating, I will be proud to have contributed something. But you know what? Call Craig Roberts at the University of Liverpool, he’s more up to date on the research.”
“THERE ARE LOTS of inconsistencies in the results,” says Roberts, an anthropologist, ten minutes later, referring to an article in which he reviews all the experiments and observations in relation to mate choice and biology.
“It’s all a big scam,” he adds, about the scheme to use the gene as a dating compatibility test. “We’re not yet at a stage where we can say that HLA differences have a practical significance. But sex sells, and so does science. People are gullible, and someone is going to make a lot of money off this.”
Roberts sounds put out, but he suddenly strikes a plaintive tone. “Maybe I’m just jealous,” he says, admitting that he himself tried his hand at the business. A few years ago, he was thinking about starting something along the line of a dating service, and even got a business partner to help realize the project. “But, ultimately, I couldn’t make myself do it, because I could see there weren’t enough data. I’m too ethical for my own good.”
Well, we all have our cross to bear.
“Think of all the noise. GenePartner’s website talks about social and biological compatibility, but on the biology end, they don’t take into consideration what we know about preferences with respect to faces and how it all goes together with HLA genes.”
He has a point. A number of studies have been made on which faces attract us, and when you begin to gene-test the research subjects, it typically proves that the faces people find most attractive belong to people whose HLA genes resemble their own. Roberts, who has done this sort of experiment himself, has a theory that the two preferences guide us down a middle path. If we prefer faces of people with similar HLA genes but scents of people with maximally different HLA genes, we may, on average, choose partners who are in the middle – avoiding the extremes.
“I just don’t know where the gold is here with partner preferences,” Roberts says, somewhat discouraged. “There are a lot of laboratory experiments and dirty T-shirts, but we know very little about how it works in real life.”
I ask what he thinks about the sensational 2006 study from the University of Arizona, in which a group of researchers found that couples who had a large difference in their HLA genes not only reported a better relationship but also had a better sex life than couples with smaller differences. The women in particular reported more orgasms. These same women also cheated less than women who share more HLA genes with their husbands.
“Yes!” Roberts spontaneously replies. “That is an excellent study, and I would love to get the opportunity to repeat it with a different group of people and expand the experiment’s design. I believe that you should go beyond sexual satisfaction and relationships and look at whether the offspring, in fact, are healthier and more disease-resistant, if the parents have big differences in their HLA genes. This would address some of the evolutionary theories directly.”
In the meantime, however, Roberts is applying for a grant to investigate what people actually think about genes and mate choice and how they would use the information from a dating service like, say, GenePartner.
I’m struck by how old-fashioned all this sounds. So I ask Roberts if he thinks this new genetic approach will change our view of what we seek in a partner. That the venerable goal of producing “good” children is what a relationship is about.
“My gut feeling tells me that nothing will change,” he says at first, but then immediately does a half turn.
“Have you seen the clips from Good Morning America, where two daters were tested by GenePartner? These two people clearly don’t know much about genetics, but they are obviously thinking about a genetically suitable partner.”
I promise to watch it, and Roberts’ farewell sounds like a paraphrase of Wedekind’s: “I feel convinced that an underlying genetic component to the attraction we feel for each other will be found. We just don’t have the right take on it yet.”
THAT TAKE IS what they’re trying to find at Sood-Oberleimsbach, an industrial district near Zürich, where GenePartner has its head
quarters in a box-like office building. The company’s total manpower proves to be two women: the director, Joelle Apter, and the head of research, Tamara Brown. It was Brown who kindly arranged to expedite the analysis of the romantic compatibility of the HLA genes in me, my boyfriend, and my eager colleague J. She corresponds to none of my expectations for a sharp player at the somewhat dubious end of the gene industry. She has a delicate, pale, and well-scrubbed face that could easily belong to a Renaissance Madonna, but she is dressed in loose jeans and a much-too-roomy grey sweater. And she has a tendency to jabber away candidly about this and that.
“When I was in my twenties and didn’t have a boyfriend, I had a plan. If I hadn’t found a husband before I hit thirty, I would have a baby by a sperm donor. And I thought ‘why not choose a black man?’ The mix is so beautiful, don’t you think?”
The plan never amounted to anything, it turns out. Above her desk, there are some photographs of a blond – and very attractive – man. It was after catching him via Internet dating that Brown spoke to Apter about whether Wedekind’s laboratory findings could, perhaps, be applied in the big, bad world. “We didn’t know whether it would work, because it had to do with odors. But we wanted to investigate whether it actually meant something for real couples.”
First, in 2003, they established a company, the Swiss Institute for Behavioral Genetics and immediately advertised for couples who had been together for between five and thirty years and who wanted to participate in a research project. It took a long time to find subjects, admits Brown, without, however, revealing how many they actually got hold of. “Sufficiently many to get statistically tenable material,” she merely says.
Everyone was HLA-tested and completed an interminably long questionnaire that was supposed to characterize their relationship and how satisfying it was for both parties. Had it been love at first sight or was it a friendship that had grown into something else? How would they describe the state of their sex life, how many children did they have, how many years in between the births?