You Can Learn a Lot About Yourself From a DNA Test. Here’s What Your Genes Cannot Tell You

“Have you found an article of clothing with a suspicious stain?” asks the website of one Florida-based company called All About Truth DNA Services, which informs readers that “aprrpoximately [sic] 60% of husbands and 40% of wives will have an affair at some point,” and recommends consumers wait for their “suspicious item” to dry and then send it in for testing. Also accepted: cigarette butts, toothpicks, hair.

The landscape of the consumer genomics market now would have been barely recognizable a decade ago. One study by scholar Andelka Phillips, then at the University of Oxford, found that as of January 2016, at least 246 genetics testing companies across the globe were selling their wares directly to customers online. Not all DNA testing companies offer services related to predicting ethnicity and finding relatives; indeed, the spectrum of services they offer is dizzying, and their usefulness and accuracy sometimes dubious. They range from the paternity tests you can pick up at Walgreens to tests that look specifically for African or Native American ancestry to others promising DNA-based matchmaking services. Phillips’s survey placed consumer DNA tests into a long list of categories that included “child talent,” “nutrigenetic” and, most ominously, “surreptitious.” These tests are generally lightly regulated, with the exception of health risk testing such as that offered by 23andMe, which is regulated in the United States by the Food and Drug Administration. The catchiest company names I’ve seen are “She Cheated” and “Who’zTheDaddy?”

While the lion’s share of DNA-testing companies cater to questions of ancestry, health, paternity and relatedness, much of the emerging consumer genomics market falls into lifestyle and fitness categories, encompassing products The Atlantic’s Sarah Zhang has likened to horoscopes: “vague, occasionally informative, sometimes amusing.” Their claims, and the science used to back them up, are of varying quality. Some tests, met with horror by a wide swath of researchers, promise to offer insight into children’s athletic ability. One company offers an “Inborn Talent Genetic Test” for children, to help with career profiling—the better to maximize “the chances of them becoming an elite in life.” Marketing “faux scientific authority,” these kinds of tests aren’t just harmless entertainment, warns a paper by Eric Topol and Emily Spencer of Scripps Research Translational Institute; they threaten to diminish consumer confidence in the clinical genetic tests that doctors order to guide medical decisions.

The landscape is confusing for the average consumer, and it can be hard to tell which genetic tests to take seriously. Large ancestry-testing companies, like AncestryDNA and 23andMe, may be characterized as “recreational,” but they employ teams of scientists and rely on robust data to understand genetic relatedness and to track patterns of ancestral heritage (even if the latter is imperfect and constantly being refined). On the other hand, when 23andMe announced it was teaming up with a health-coaching app and allowing customers to integrate their genetic results to help generate personalized diet and exercise advice — a product that focuses on wellness, so not regulated by the FDA — a number of geneticists were skeptical, concerned the company was getting ahead of research.

What is a consumer to believe? A few years ago, Helix, originally a spin-out of genomics giant Illumina (which makes many of the chips and machines used to analyze DNA), unveiled a “DNA app store” allowing third-party companies to sell products off its DNA testing. While these included the Mayo Clinic GeneGuide, a test that requires the sign-off of a physician and, with the help of Mayo Clinic professionals, interprets your genetic material for insights into things like disease risk and carrier screening, they also included the Vinome “wine explorer,” which claimed your genetic data could help predict what wine you’d like, a concept that University of North Carolina geneticist Jim Evans described to the publication STAT as “completely silly.” Helix has since announced a shift away from this “consumer-initiated” model, but there is still a lot of confusion over what genetic testing can and should be able to tell us.

One spring day, I found myself watching an ad for a special partnership between 23andMe and Lexus, which promised to find cars optimized to people’s genetics. It’s a credit to how out-there some DNA testing claims have become that it took me a few seconds to realize this was an April Fool’s joke. As ludicrous and playful as that ad turned out to be (the driver licks the steering wheel to start the engine), it hit on a deeper message rooted in a suite of cultural messages we get about our genes. Consider the marketing campaigns that consumer genetics companies actually do run. During the 2018 FIFA Men’s World Cup, for which the U.S. team failed to qualify, 23andMe urged people to root for a team “based on your genetic ancestry”—they called this campaign “Root for your Roots.” AncestryDNA has partnered with Spotify to create custom playlists based on the ancestral regions that customers hail from. “Solidify a true connection to the motherland,” suggests one ad by a company called African Ancestry. “Know who you are”—as if DNA might know us better than we know ourselves, might act as a kind of historical id, reminding us of cultural affinities forgotten over generations but remembered in our cells.

These efforts are targeting—and reinforcing—a deep-seated belief that if we peer closely enough, we’ll be able to decipher nearly everything about ourselves, our likes and loves, from the ACGTs along the strands of the double helix of our DNA molecules. It is an idea we’ve held for decades. In The DNA Mystique: The Gene as a Cultural Icon, published in 1995, scholars Dorothy Nelkin and M. Susan Lindee warned of the rise of genetic essentialism. Examining portrayals of the gene in mass culture, they found a tendency to point to genes as the explanation for “obesity, criminality, shyness, directional ability, political leanings, and preferred styles of dressing. There are selfish genes, pleasure-seeking genes, violence genes, celebrity genes . . .” In popular portrayal, good genes and bad genes lead to good and bad traits.

We’re such believers in genes that a recent Stanford University study found that informing people of their genetic predispositions for certain traits—rather, misinforming them, by telling them whether they had certain gene variants associated with exercise capacity and obesity, regardless of their actual results—influenced their actual physiology. Those told they had low-endurance versions of a gene variant did worse on a treadmill test, with poorer endurance and worse lung function (even if they didn’t have that gene variant). Those told they had a variant that made them feel easily sated felt fuller on average after being given a meal, and tests revealed their bodies had produced more of a hormone that correlates with feelings of fullness. By believing they were genetically destined for something, these subjects appear to have made it true.

In their book, Nelkin and Lindee looked back at the eugenics movement earlier in the century and saw thematic links between the 1990s obsession with genetics and those old notions of heredity. Yesterday’s “Better Babies” – showcased through early 20th century baby-rating contests with points deducted for “defects” like scaly skin and delayed teething – were “still a highly desired reproductive commodity.” Yesterday’s “feebleminded” women, forcibly sterilized so as not to pass what eugenicists saw as their problems on to the next generation, had been transformed into contemporary welfare mothers said to be birthing tomorrow’s poor and criminal classes. “Ideas about heredity have as much to do with social meaning as they do with scientific research,” they wrote.

Beneath all this, the authors argued, lay the mystique of the genes: “DNA has assumed a cultural meaning similar to that of the biblical soul. It has become a sacred entity, a way to explore fundamental questions about human life, to define the essence of human existence.” Like the soul, DNA in this reading has a moral meaning and has implications not only for a person’s sense of identity but for her place in society. Twenty-five years after The DNA Mystique came out, we still talk about DNA in quasi-religious terms—“the language,” as Bill Clinton once put it, “in which God created life.” And perhaps there’s something deeply human about this. Cultural psychologist Steven J. Heine has written that “in every society that has been investigated, there is clear evidence to show that we are predisposed to think of the world as emerging from hidden underlying essences”—whether that be blood or chi, humors or souls. Essentialism “is one of the most persistent and widely documented psychological biases.”

Kristen V. Brown, a Bloomberg journalist who covers the intersection of technology, business and health, told me she blamed some of this essentialist thinking on the Human Genome Project, a massive, multinational effort to sequence the more than 3 billion base pairs that make up the genetic blueprint for a human being, which was launched in 1990 and completed in 2003. “Because part of the way that the Human Genome Project was sold to the masses was this idea that your genome explains everything,” Brown says. “And then we decoded most of the important parts and were like, ‘Shit, this still doesn’t explain everything.’ . . . But that was the marketing message and it was a good one, and it stuck.”

So when companies urge people to root for a soccer team based on genetic heritage, or promise an exercise plan based on their DNA, this homes in on an idea that already holds great currency in the popular imagination. We are eager to know more about ourselves, and within the consumer space, ancestry testing (seemingly less fraught than health testing) appears to be driving the market for self-discovery. An Ancestry ad during the 2018 holiday season showed Kelly Ripa ordering biscotti in imperfect Italian, since she had just discovered she was “74% Italian!” What fun! Who wouldn’t want an excuse to expand their diet of baked goods?

The market may change over time, of course. As our understanding of genetics improves, things like pharmacogenomics (the relationship between drugs and genes) and nutrigenomics (the interplay between nutrition and genes) may become much bigger forces. What’s now considered “recreational” health testing may become more clinically relevant, and the genetic health market in general may prove to be bigger than that for ancestry and genealogy. But for now, as University College London researcher and genetic genealogist Debbie Kennett points out, the largest genomic dataset in the world isn’t in the hands of governments, pharmaceutical companies or research organizations. “Instead,” she writes, “it is the ancestry companies which have been accumulating most of the genetic data.”

In many cases, consumers who engage in ancestry testing are making discoveries far more profound than Kelly Ripa made. Over 30 million people have tested through companies like Ancestry and 23andMe, receiving those “ethnicity estimate” pie charts as well as lists of genetic relatives, and sometimes learning that their families aren’t exactly what they thought they were. These revelations can be heartwarming, and they can be heartbreaking. The hundreds of stories of rifts, reunions and reconciliations I’ve heard over the past few years are testament to the power of spitting into a vial. Meanwhile, in the last two years, law enforcement has begun accessing certain quasi-public databases to use genetic information that was gathered for family history purposes to solve cold cases, opening up debates about privacy, civil liberties and consent.

Despite news of a recent slowdown in sales, the number of people in these databases can only get bigger – though how much bigger will depend on many of the human factors at play in the quest for more information. Will growth taper off because the early adopters have already bought spit kits, while more casual consumers are scared off by privacy concerns? Or will an ongoing appetite for self-discovery, for health insights, for greater certainty about the past and the future, drive us to look for more answers within ourselves?

We are only at the beginning of this genetic reckoning.

Adapted excerpt from The Lost Family: How DNA Testing is Upending Who We Are by Libby Copeland. To be published on March 3, 2020 by Abrams Press © 2020 Libby Copeland. Used by permission of Abrams, an imprint of Harry N. Abrams, Inc., New York. All rights reserved.