A woman gives a DNA sample at a Pheramor-sponsored event.

(Pheramor)


Brittany Barreto first got the idea to make a DNA-based dating platform nearly 10 years ago when she was in a college seminar on genetics. She joked that it would be called GeneHarmony.com.

Pheramor and startups, like DNA Romance and Instant Chemistry, both based in Canada, claim to match you to a romantic partner based on your genetics.

The idea stuck with her while she was getting her PhD in genetics at Baylor College of Medicine, and in March 2018, she launched Pheramor, a dating app that measures compatibility based on physical chemistry and what the company calls "social alignment."

"I wanted to use genetics and science to help people connect more. Our world is so hungry for connection," says Barreto, who serves as Pheramor's CEO.

With the direct-to-consumer genetic testing market booming, more and more companies are looking to capitalize on the promise of DNA-based services. Pheramor and startups, like DNA Romance and Instant Chemistry, both based in Canada, claim to match you to a romantic partner based on your genetics. It's an intriguing alternative to swiping left or right in hopes of finding someone you're not only physically attracted to but actually want to date. Experts say the science behind such apps isn't settled though.

For $40, Pheramor sends you a DNA kit to swab the inside of your cheek. After you mail in your sample, Pheramor analyzes your saliva for 11 different HLA genes, a fraction of the more than 200 genes that are thought to make up the human HLA complex. These genes make proteins that regulate the immune system by helping protect against invading pathogens.

It takes three to four weeks to get the results backs. In the meantime, users can still download the app and start using it before their DNA results are ready. The app asks users to link their social media accounts, which are fed into an algorithm that calculates a "social alignment." The algorithm takes into account the hashtags you use, your likes, check-ins, posts, and accounts you follow on Facebook, Twitter, and Instagram.

The DNA test results and social alignment algorithm are used to calculate a compatibility percentage between zero and 100. Barreto said she couldn't comment on how much of that score is influenced by the algorithm and how much comes from what the company calls genetic attraction. "DNA is not destiny," she says. "It's not like you're going to swab and I'll send you your soulmate."

Despite its name, Pheramor doesn't actually measure pheromones, chemicals released by animals that affect the behavior of others of the same species. That's because human pheromones have yet to be identified, though they've been discovered throughout the animal kingdom in moths, mice, rabbits, pigs, and many other insects and mammals. The HLA genes Pheramor analyzes instead are the human version of the major histocompatibility complex (MHC), a gene group found in many species.

The connection between HLA type and attraction goes back to the 1970s, when researchers found that inbred male mice preferred to mate with female mice with a different MHC rather than inbred female mice with similar immune system genes. The researchers concluded that this mating preference was linked to smell. The idea is that choosing a mate with different MHC genes gives animals an evolutionary advantage in terms of immune system defense.

The couples who had more dissimilar HLA types reported a more satisfied sex life and satisfied partnership, but it was a small effect.

In the 1990s, Swiss scientists wanted to see if body odor also had an effect on human attraction. In a famous experiment known as the "sweaty T-shirt study", they recruited 49 women to sniff sweaty, unwashed T-shirts from 44 men and put each in a box with a smelling hole and describe the odors of every shirt. The study found that women preferred the scents of T-shirts worn by men who were immunologically different from them compared to men whose HLA genes were similar to their own.

"The idea is, if you are very similar with your partner in HLA type then your offspring is similar in terms of HLA. This reduces your resistance against pathogens," says Illona Croy, a psychologist at the Technical University of Dresden who has studied HLA type in relation to sexual attraction in humans.

In a 2016 study Pheramor cites on its website, Croy and her colleagues tested the HLA types of 250 couples—all of them university students—and asked them how satisfied they were with their partnerships, with their sex lives, and with the odors of their partners. The couples who had more dissimilar HLA types reported a more satisfied sex life and satisfied partnership, but Croy cautions that it was a small effect. "It's not like they were super satisfied or not satisfied at all. It's a slight difference," she says.

Croy says we're much more likely to choose a partner based on appearance, sense of humor, intelligence and common interests.

Other studies have reported no preference for HLA difference in sexual attraction. Tristram Wyatt, a zoologist at the University of Oxford in the U.K. who studies animal pheromones, says it's been difficult to replicate the original T-shirt study. And one of the caveats of the original study is that women who were taking birth control pills preferred men who were more immunologically similar.

"Certainly, we learn to really like the smell of our partners," Wyatt says. "Whether it's the reason for choosing them in the first place, we really don't know."

Wyatt says he's skeptical of DNA-based dating apps because there are many subtypes of HLA genes, meaning there's a fairly low chance that your HLA type and your romantic partner's would be an exact match, anyway. It's why finding a suitable match for a bone marrow transplant is difficult; a donor's HLA type has to be the same as the recipient's.

"What it means is that since we're all different, it's hard statistically to say who the best match will be," he says.

DNA-based dating apps haven't yet gone mainstream, but some people seem willing to give them a try. Since Pheramor's launch a little over a year ago, about 10,000 people have signed up to use the app, about half of which have taken the DNA test, Barreto says. By comparison, an estimated 50 million people use Tinder, which has been around since 2012, and about 40 million people are on Bumble, which was released in 2014.

In April, Barreto launched a second service, this one for couples, called WeHaveChemistry.com. A $139 kit includes two genetic tests, one for you and your partner, and a detailed DNA report on your sexual compatibility.

Unlike the Phermor app, WeHaveChemistry doesn't provide users with a numeric combability score but instead makes personalized recommendations based on your genetic results. For instance, if the DNA test shows that your HLA genes are similar, Barreto says, "We might recommend pheromone colognes, working out together, or not showering before bed to get your juices running."

Despite her own research on HLA and sexual compatibility, Croy isn't sure how knowing HLA type will help couples. However, some researchers are doing studies on whether HLA types are related to certain cases of infertility, and this is where a genetic test might be very useful, says Croy.

"Otherwise, I think it doesn't matter whether we're HLA compatible or not," she says. "It might give you one possible explanation about why your sexual life isn't as satisfactory as it could be, but there are many other factors that play a role."

Emily Mullin
Emily Mullin is a freelance science journalist based in Maryland. She most often writes about the cutting edge of medicine and biotechnology. Previously, she was the associate editor for biomedicine at MIT Technology Review. Her stories have also appeared in The Washington Post, Scientific American, National Geographic, The Atlantic and elsewhere.
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A hacker activating a 3D rendering of DNA data.

(© Production Perig/Fotolia)


In February 2015, the health insurer Anthem revealed that criminal hackers had gained access to the company's servers, exposing the personal information of nearly 79 million patients. It's the largest known healthcare breach in history.

FBI agents worry that the vast amounts of healthcare data being generated for precision medicine efforts could leave the U.S. vulnerable to cyber and biological attacks.

That year, the data of millions more would be compromised in one cyberattack after another on American insurers and other healthcare organizations. In fact, for the past several years, the number of reported data breaches has increased each year, from 199 in 2010 to 344 in 2017, according to a September 2018 analysis in the Journal of the American Medical Association.

The FBI's Edward You sees this as a worrying trend. He says hackers aren't just interested in your social security or credit card number. They're increasingly interested in stealing your medical information. Hackers can currently use this information to make fake identities, file fraudulent insurance claims, and order and sell expensive drugs and medical equipment. But beyond that, a new kind of cybersecurity threat is around the corner.

Mr. You and others worry that the vast amounts of healthcare data being generated for precision medicine efforts could leave the U.S. vulnerable to cyber and biological attacks. In the wrong hands, this data could be used to exploit or extort an individual, discriminate against certain groups of people, make targeted bioweapons, or give another country an economic advantage.

Precision medicine, of course, is the idea that medical treatments can be tailored to individuals based on their genetics, environment, lifestyle or other traits. But to do that requires collecting and analyzing huge quantities of health data from diverse populations. One research effort, called All of Us, launched by the U.S. National Institutes of Health last year, aims to collect genomic and other healthcare data from one million participants with the goal of advancing personalized medical care.

Other initiatives are underway by academic institutions and healthcare organizations. Electronic medical records, genetic tests, wearable health trackers, mobile apps, and social media are all sources of valuable healthcare data that a bad actor could potentially use to learn more about an individual or group of people.

"When you aggregate all of that data together, that becomes a very powerful profile of who you are," Mr. You says.

A supervisory special agent in the biological countermeasures unit within the FBI's weapons of mass destruction directorate, it's Mr. You's job to imagine worst-case bioterror scenarios and figure out how to prevent and prepare for them.

That used to mean focusing on threats like anthrax, Ebola, and smallpox—pathogens that could be used to intentionally infect people—"basically the dangerous bugs," as he puts it. In recent years, advances in gene editing and synthetic biology have given rise to fears that rogue, or even well-intentioned, scientists could create a virulent virus that's intentionally, or unintentionally, released outside the lab.

"If a foreign source, especially a criminal one, has your biological information, then they might have some particular insights into what your future medical needs might be and exploit that."

While Mr. You is still tracking those threats, he's been traveling around the country talking to scientists, lawyers, software engineers, cyber security professionals, government officials and CEOs about new security threats—those posed by genetic and other biological data.

Emerging threats

Mr. You says one possible situation he can imagine is the potential for nefarious actors to use an individual's sensitive medical information to extort or blackmail that person.

"If a foreign source, especially a criminal one, has your biological information, then they might have some particular insights into what your future medical needs might be and exploit that," he says. For instance, "what happens if you have a singular medical condition and an outside entity says they have a treatment for your condition?" You could get talked into paying a huge sum of money for a treatment that ends up being bogus.

Or what if hackers got a hold of a politician or high-profile CEO's health records? Say that person had a disease-causing genetic mutation that could affect their ability to carry out their job in the future and hackers threatened to expose that information. These scenarios may seem far-fetched, but Mr. You thinks they're becoming increasingly plausible.

On a wider scale, Kavita Berger, a scientist at Gryphon Scientific, a Washington, D.C.-area life sciences consulting firm, worries that data from different populations could be used to discriminate against certain groups of people, like minorities and immigrants.

For instance, the advocacy group Human Rights Watch in 2017 flagged a concerning trend in China's Xinjiang territory, a region with a history of government repression. Police there had purchased 12 DNA sequencers and were collecting and cataloging DNA samples from people to build a national database.

"The concern is that this particular province has a huge population of the Muslim minority in China," Ms. Berger says. "Now they have a really huge database of genetic sequences. You have to ask, why does a police station need 12 next-generation sequencers?"

Also alarming is the potential that large amounts of data from different groups of people could lead to customized bioweapons if that data ends up in the wrong hands.

Eleonore Pauwels, a research fellow on emerging cybertechnologies at United Nations University's Centre for Policy Research, says new insights gained from genomic and other data will give scientists a better understanding of how diseases occur and why certain people are more susceptible to certain diseases.

"As you get more and more knowledge about the genomic picture and how the microbiome and the immune system of different populations function, you could get a much deeper understanding about how you could target different populations for treatment but also how you could eventually target them with different forms of bioagents," Ms. Pauwels says.

Economic competitiveness

Another reason hackers might want to gain access to large genomic and other healthcare datasets is to give their country a leg up economically. Many large cyber-attacks on U.S. healthcare organizations have been tied to Chinese hacking groups.

"This is a biological space race and we just haven't woken up to the fact that we're in this race."

"It's becoming clear that China is increasingly interested in getting access to massive data sets that come from different countries," Ms. Pauwels says.

A year after U.S. President Barack Obama conceived of the Precision Medicine Initiative in 2015—later renamed All of Us—China followed suit, announcing the launch of a 15-year, $9 billion precision health effort aimed at turning China into a global leader in genomics.

Chinese genomics companies, too, are expanding their reach outside of Asia. One company, WuXi NextCODE, which has offices in Shanghai, Reykjavik, and Cambridge, Massachusetts, has built an extensive library of genomes from the U.S., China and Iceland, and is now setting its sights on Ireland.

Another Chinese company, BGI, has partnered with Children's Hospital of Philadelphia and Sinai Health System in Toronto, and also formed a collaboration with the Smithsonian Institute to sequence all species on the planet. BGI has built its own advanced genomic sequencing machines to compete with U.S.-based Illumina.

Mr. You says having access to all this data could lead to major breakthroughs in healthcare, such as new blockbuster drugs. "Whoever has the largest, most diverse dataset is truly going to win the day and come up with something very profitable," he says.

Some direct-to-consumer genetic testing companies with offices in the U.S., like Dante Labs, also use BGI to process customers' DNA.

Experts worry that China could race ahead the U.S. in precision medicine because of Chinese laws governing data sharing. Currently, China prohibits the exportation of genetic data without explicit permission from the government. Mr. You says this creates an asymmetry in data sharing between the U.S. and China.

"This is a biological space race and we just haven't woken up to the fact that we're in this race," he said in January at an American Society for Microbiology conference in Washington, D.C. "We don't have access to their data. There is absolutely no reciprocity."

Protecting your data

While Mr. You has been stressing the importance of data security to anyone who will listen, the National Academies of Sciences, Engineering, and Medicine, which makes scientific and policy recommendations on issues of national importance, has commissioned a study on "safeguarding the bioeconomy."

In the meantime, Ms. Berger says organizations that deal with people's health data should assess their security risks and identify potential vulnerabilities in their systems.

As for what individuals can do to protect themselves, she urges people to think about the different ways they're sharing healthcare data—such as via mobile health apps and wearables.

"Ask yourself, what's the benefit of sharing this? What are the potential consequences of sharing this?" she says.

Mr. You also cautions people to think twice before taking consumer DNA tests. They may seem harmless, he says, but at the end of the day, most people don't know where their genetic information is going. "If your genetic sequence is taken, once it's gone, it's gone. There's nothing you can do about it."

Emily Mullin
Emily Mullin is a freelance science journalist based in Maryland. She most often writes about the cutting edge of medicine and biotechnology. Previously, she was the associate editor for biomedicine at MIT Technology Review. Her stories have also appeared in The Washington Post, Scientific American, National Geographic, The Atlantic and elsewhere.

Theo Roth.

(Photo credit: Noah Berger/UCSF)


After months of looking at dead cells under a microscope, Theo Roth finally glimpsed what he had been hoping to see—flickers of green. His method was working.

"If we can go into the cell and add in new code and instructions, now we can give it whatever new functions we want."

When Roth joined the laboratory of Alex Marson at the University of California, San Francisco in June 2016, he set to work trying to figure out a new way to engineer human T cells, a type of white blood cell that's an important part of the immune system. If he succeeded, the resulting approach could make it easier and faster for scientists to develop and test cell and gene therapies, new treatments that involve genetically reprogramming the body's own cells.

For decades, researchers have been using engineered viruses to bestow human cells with new genetic characteristics. These so-called viral vectors "infect" human cells, transferring whatever new genetic material scientists put into them. The idea is that this new DNA could give T cells a boost to better fight diseases like cancer and HIV.

Several successful clinical trials have used virally-modified human T cells, and in fact, the U.S. Food and Drug Administration last year approved two such groundbreaking cancer gene therapies, Kymriah and Yescarta. But the process of genetically manipulating cells with viruses is expensive and time-consuming. In addition, viruses tend to randomly insert DNA with little predictability.

"What Theo wanted to do was to paste in big sequences of DNA at a targeted site without viruses," says Marson, an associate professor of microbiology and immunology. "That would have the benefit of being able to rewrite a specific site in the genome and do it flexibly and quickly without having to make a new virus for every site you want to manipulate."

Scientists have for a while been interested in non-viral engineering methods, but T cells are fragile and notoriously difficult to work with.

Previously, Marson's lab had collaborated with CRISPR pioneer Jennifer Doudna and her team at the University of California, Berkeley to use an electrical pulse together with CRISPR components to knock out certain genes. They also found some success with inserting very small pieces of DNA into a targeted site.

But Roth, a 27-year-old graduate student at UCSF pursuing MD and PhD degrees, was determined to figure out how to paste in much bigger sequences of genetic information. Marson says it was an "ambitious" goal. Scientists had tried before, but found that stuffing large chunks of DNA into T cells would quickly kill them.

"If we can go into the cell and add in new code and instructions, now we can give it whatever new functions we want," Roth says. "If you can add in new DNA sequences at the site that you want, then you have a much greater capacity to generate a cell that's going to be therapeutic or curative for a disease."

"He has already made his mark on the field."

So Roth began experimenting with hundreds of different variables a week, trying to find the right conditions to allow him to engineer T cells without the need for viruses. To know if the technique was working, Roth and his colleagues used a green fluorescent protein that would be expressed in cells that had successfully been modified.

"We went from having a lot of dead cells that didn't have any green to having maybe 1 percent of them being green," Roth says. "At that stage we got really excited."

After nearly a year of testing, he and collaborators found a combination of T cell ratios and DNA quantity mixed with CRISPR and zaps of electricity that seemed to work. These electrical pulses, called electroporation, deliver a jolt to cells that makes their membranes temporarily more permeable, allowing the CRISPR system to slip through. Once inside cells, CRISPR seeks out a specific place in the genome and makes a programmed, precise edit.

Roth and his colleagues used the approach to repair a genetic defect in T cells taken from children with a rare autoimmune disease and also to supercharge T cells so that they'd seek out and selectively kill human cancer cells while leaving healthy cells intact. In mice transplanted with human melanoma tissue, the edited T cells went to straight to the cancerous cells and attacked them. The findings were published in Nature in July.

Marson and Roth think even a relatively small number of modified T cells could be effective at treating some cancers, infections, and autoimmune diseases.

Roth is now working with the Parker Institute for Cancer Immunotherapy in San Francisco to engineer cells to treat a variety of cancers and hopefully commercialize his technique. Fred Ramsdell, vice president at the Parker Institute, says he's impressed by Roth's work. "He has already made his mark on the field."

Right now, there's a huge manufacturing backlog for viruses. If researchers want to start a clinical trial to test a new gene or cell therapy, they often have to wait a year to get the viruses they need.

"I think the biggest immediate impact is that it will lower the cost of a starting an early phase clinical trial."

Ramsdell says what Roth's findings allow researchers to do is engineer T cells quickly and more efficiently, cutting the time it takes to make them from several months to just a few weeks. That will allow researchers to develop and test several potential therapies in the lab at once.

"I think the biggest immediate impact is that it will lower the cost of a starting an early phase clinical trial," Roth says.

This isn't the first time Roth's work has been in the spotlight. As an undergraduate at Stanford University, he made significant contributions to traumatic brain injury research by developing a mouse model for observing the brain's cellular response to a concussion. He started the research, which was also published in Nature, the summer before entering college while he was an intern in Dorian McGavern's lab at the National Institutes of Health.

When Roth entered UCSF as a graduate student, his scientific interests shifted.

"It's definitely a big leap" from concussion research, says McGavern, who still keeps in touch with Roth. But he says he's not surprised about Roth's path. "He's absolutely tireless when it comes to the pursuit of science."

Roth says he's optimistic about the potential for gene and cell therapies to cure patients. "I want to try to figure out what one of the next therapies we should put into patients should be."

Emily Mullin
Emily Mullin is a freelance science journalist based in Maryland. She most often writes about the cutting edge of medicine and biotechnology. Previously, she was the associate editor for biomedicine at MIT Technology Review. Her stories have also appeared in The Washington Post, Scientific American, National Geographic, The Atlantic and elsewhere.