Is It Possible to Predict Your Face, Voice, and Skin Color from Your DNA?
Renowned genetics pioneer Dr. J Craig Venter is no stranger to controversy.
Back in 2000, he famously raced the public Human Genome Project to decode all three billion letters of the human genome for the first time. A decade later, he ignited a new debate when his team created a bacterial cell with a synthesized genome.
Most recently, he's jumped back into the fray with a study in the September issue of the Proceedings of the National Academy of Sciences about the predictive potential of genomic data to identify individual traits such as voice, facial structure and skin color.
The new study raises significant questions about the privacy of genetic data.
His study applied whole-genome sequencing and statistical modeling to predict traits in 1,061 people of diverse ancestry. His approach aimed to reconstruct a person's physical characteristics based on DNA, and 74 percent of the time, his algorithm could correctly identify the individual in a random lineup of 10 people from his company's database.
While critics have been quick to cast doubt on the plausibility of his claims, the ability to discern people's observable traits, or phenotypes, from their genomes may grow more precise as technology improves, raising significant questions about the privacy and usage of genetic information in the long term.
J. Craig Venter showing slides from his recent study on facial prediction at the Summit Conference in Los Angeles on Nov. 3, 2017.
(Courtesy of Kira Peikoff)
Critics: Study Was Incomplete, Problematic
Before even redressing these potential legal and ethical considerations, some scientists simply said the study's main result was invalid. They pointed out that the methodology worked much better in distinguishing between people of different ethnicities than those of the same ethnicity. One of the most outspoken critics, Yaniv Erlich, a geneticist at Columbia University, said, "The method doesn't work. The results were like, 'If you have a lineup of ten people, you can predict eight."
Erlich, who reviewed Venter's paper for Science, where it was rejected, said that he came up with the same results—correctly predicting eight of ten people—by just looking at demographic factors such as age, gender and ethnicity. He added that Venter's recent rebuttal to his criticism was that 'Once we have thousands of phenotypes, it might work better.' But that, Erlich argued, would be "a major breach of privacy. Nobody has thousands of phenotypes for people."
Other critics suggested that the study's results discourage the sharing of genetic data, which is becoming increasingly important for medical research. They go one step further and imply that people's possible hesitation to share their genetic information in public databases may actually play into Venter's hands.
Venter's own company, Human Longevity Inc., aims to build the world's most comprehensive private database on human genotypes and phenotypes. The vastness of this information stands to improve the accuracy of whole genome and microbiome sequencing for individuals—analyses that come at a hefty price tag. Today, Human Longevity Inc. will sequence your genome and perform a battery of other health-related tests at an entry cost of $4900, going up to $25,000. Venter initially agreed to comment for this article, but then could not be reached.
"The bigger issue is how do we understand and use genetic information and avoid harming people."
Opens Up Pandora's Box of Ethical Issues
Whether Venter's study is valid may not be as important as the Pandora's box of potential ethical and legal issues that it raises for future consideration. "I think this story is one along a continuum of stories we've had on the issue of identifiability based on genomic information in the past decade," said Amy McGuire, a biomedical ethics professor at Baylor College of Medicine. "It does raise really interesting and important questions about privacy, and socially, how we respond to these types of scientific advancements. A lot of our focus from a policy and ethics perspective is to protect privacy."
McGuire, who is also the Director of the Center for Medical Ethics and Health Policy at Baylor, added that while protecting privacy is very important, "the bigger issue is how do we understand and use genetic information and avoid harming people." While we've taken "baby steps," she said, towards enacting laws in the U.S. that fight genetic determinism—such as the Genetic Information and Nondiscrimination Act, which prohibits discrimination based on genetic information in health insurance and employment—some areas remain unprotected, such as for life insurance and disability.
J. Craig Venter showing slides from his recent study on facial prediction at the Summit Conference in Los Angeles on Nov. 3, 2017.
(Courtesy of Kira Peikoff)
Physical reconstructions like those in Venter's study could also be inappropriately used by law enforcement, said Leslie Francis, a law and philosophy professor at the University of Utah, who has written about the ethical and legal issues related to sharing genomic data.
"If [Venter's] findings, or findings like them, hold up, the implications would be significant," Francis said. Law enforcement is increasingly using DNA identification from genetic material left at crime scenes to weed out innocent and guilty suspects, she explained. This adds another potentially complicating layer.
"There is a shift here, from using DNA sequencing techniques to match other DNA samples—as when semen obtained from a rape victim is then matched (or not) with a cheek swab from a suspect—to using DNA sequencing results to predict observable characteristics," Francis said. She added that while the former necessitates having an actual DNA sample for a match, the latter can use DNA to pre-emptively (and perhaps inaccurately) narrow down suspects.
"My worry is that if this [the study's methodology] turns out to be sort-of accurate, people will think it is better than what it is," said Francis. "If law enforcement comes to rely on it, there will be a host of false positives and false negatives. And we'll face new questions, [such as] 'Which is worse? Picking an innocent as guilty, or failing to identify someone who is guilty?'"
Risking Privacy Involves a Tradeoff
When people voluntarily risk their own privacy, that involves a tradeoff, McGuire said. A 2014 study that she conducted among people who were very sick, or whose children were very sick, found that more than half were willing to share their health information, despite concerns about privacy, because they saw a big benefit in advancing research on their conditions.
"We've focused a lot of our policy attention on restricting access, but we don't have a system of accountability when there's a breach."
"To make leaps and bounds in medicine and genomics, we need to create a database of millions of people signing on to share their genetic and health information in order to improve research and clinical care," McGuire said. "They are going to risk their privacy, and we have a social obligation to protect them."
That also means "punishing bad actors," she continued. "We've focused a lot of our policy attention on restricting access, but we don't have a system of accountability when there's a breach."
Even though most people using genetic information have good intentions, the consequences if not are troubling. "All you need is one bad actor who decimates the trust in the system, and it has catastrophic consequences," she warned. That hasn't happened on a massive scale yet, and even if it did, some experts argue that obtaining the data is not the real risk; what is more concerning is hacking individuals' genetic information to be used against them, such as to prove someone is unfit for a particular job because of a genetic condition like Alzheimer's, or that a parent is unfit for custody because of a genetic disposition to mental illness.
Venter, in fact, told an audience at the recent Summit conference in Los Angeles that his new study's approach could not only predict someone's physical appearance from their DNA, but also some of their psychological traits, such as the propensity for an addictive personality. In the future, he said, it will be possible to predict even more about mental health from the genome.
What is most at risk on a massive scale, however, is not so much genetic information as demographic identifiers included in medical records, such as birth dates and social security numbers, said Francis, the law and philosophy professor. "The much more interesting and lucrative security breaches typically involve not people interested in genetic information per se, but people interested in the information in health records that you can't change."
Hospitals have been hacked for this kind of information, including an incident at the Veterans Administration in 2006, in which the laptop and external hard drive of an agency employee that contained unencrypted information on 26.5 million patients were stolen from the employee's house.
So, what can people do to protect themselves? "Don't share anything you wouldn't want the world to see," Francis said. "And don't click 'I agree' without actually reading privacy policies or terms and conditions. They may surprise you."
Scientists aim to preserve donkeys, one frozen embryo at a time
Every day for a week in 2022, Andres Gambini, a veterinarian and senior lecturer in animal science at the University of Queensland in Australia, walked into his lab—and headed straight to the video camera. Trained on an array of about 50 donkey embryos, all created by Gambini’s manual in vitro fertilization, or IVF, the camera kept an eye on their developmental progress. To eventually create a viable embryo that could be implanted into a female donkey, the embryos’ cells had to keep dividing, first in two, then in four and so on.
But the embryos weren’t cooperating. Some would start splitting up only to stop a day or two later, and others wouldn’t start at all. Every day he came in, Gambini saw fewer and fewer dividing embryos, so he was losing faith in the effort. “You see many failed attempts and get disappointed,” he says.
Gambini and his team, a group of Argentinian and Spanish researchers, were working to create these embryos because many donkey populations around the world are declining. It may sound counterintuitive that domesticated animals may need preservation, but out of 28 European donkey breeds, 20 are endangered and seven are in critical status. It is partly because of the inbreeding that happened over the course of many years and partly because in today’s Western world donkeys aren’t really used anymore.
“That's the reason why some breeds begin to disappear because humans were not really interested in having that specific breed anymore,” Gambini says. Nonetheless, in Africa, India and Latin America millions of rural families still rely on these hardy creatures for agriculture and transportation. And the only two wild donkey species—Equus africanus in Africa and Equus hemionus in Asia—are also dwindling, due to losing their habitats to human activities, diseases and slow reproduction rates. Gambini’s team wanted to create a way to preserve the animals for the future. “Donkeys are more endangered than people realize,” he says.
There’s much more to donkeys' trouble though. For the past 20 or so years, they have been facing a huge existential threat due to their hide gelatin, a compound derived from their skins by soaking and stewing. In Chinese traditional medicine, the compound, called ejiao, is believed to have a medicinal value, so it’s used in skin creams, added to food and taken in capsules. Centuries ago, ejiao was a very expensive luxury product available only for the emperor and his household. That changed in the 1990s when the Chinese economy boomed, and many people were suddenly able to afford it. “It went from a very elite product to a very popular product,” says Janneke Merkx, a campaign manager at The Donkey Sanctuary, a United Kingdom-based nonprofit organization that keeps tabs on the animals’ welfare worldwide. “It is a status symbol for gift giving.”
Having evolved in the harsh and arid mountainous terrains where food and water were scarce, donkeys are extremely adaptable and hardy. But the Donkey Sanctuary documented cases in which an entire village had their animals disappear overnight, finding them killed and skinned outside their settlement.
The Chinese donkey population was quickly decimated. Unlike many other farm animals, donkeys are finicky breeders. When stressed and unhappy, they don’t procreate, so growing them in large industrial settings isn’t possible. “Donkeys are notoriously slow breeders and really very difficult to farm,” says Merkx. “They are not the same as other livestock like sheep and pigs and cattle.” Within years the, the donkey numbers in China dropped precipitously. “China used to have the largest donkey population in the world in the 1990s. They had 11 million donkeys, and it's now down to less than 3 million, and they just can't keep up with the demand.”
To keep the ejiao conveyor going, some producers turned to the illegal wildlife trade. Poachers began to steal and slaughter donkeys from rural villages in Africa. The Donkey Sanctuary documented cases in which an entire village had their animals disappear overnight, finding them killed and skinned outside their settlement. Exactly how many creatures were lost to the skin trade to-date isn’t possible to calculate, says Faith Burden, the Donkey Sanctuary’s director of equine operations. Traditionally a poor people’s beast of burden, donkey counts are hard to keep track of. “When an animal doesn't produce meat, milk or eggs or whatever edible product, they're often less likely to be acknowledged in a government population census,” Burden says. “So reliable statistics are hard to come by.” The nonprofit estimates that about 4.8 million are slaughtered annually.
During their six to seven thousand years of domestication, donkeys rarely got the full appreciation for their services. They are often compared to horses, which doesn’t do them justice. They’re entirely different animals, Burden says. Built for speed, horses respond to predators and other dangers by running as fast as they can. Donkeys, which originate from the rocky, mountainous regions of Africa where running is dangerous, react to threats by freezing and assessing the situation for the best response. “Those so-called stubborn donkeys that won’t move as you want, they are actually thinking ‘what’s the best approach,’” Burden says. They may even choose to fight the predators rather than flee, she adds. “In some parts of the world, people use them as guard animals against things like coyotes and wolves.”
Scientists believe that domestic donkeys take their origin from Equus africanus or African wild ass, originally roaming where Kenya, Ethiopia and Eritrea are today. Having evolved in the harsh and arid mountainous terrains where food and water were scarce, they are extremely adaptable and hardy. Research finds that they can go without water for 72 hours and then drink their fill without any negative consequences. Their big jaws let them chew tough desert shrubs, which horses can’t exist on. Their large ears help dissipate heat. Their little upright hooves are a perfect fit for the uneven rocky or other dangerous grounds. Accustomed to the mountain desert climate with hot days and cold nights, they don’t mind temperature flux.
“The donkey is the most supremely adapted animal to deal with hostile conditions,” Burden says. “They can survive on much lower nutritional quality food than a cow, sheep or horse. That’s why communities living in some of the most inhospitable places will often have donkeys with them.” And that’s why losing a donkey to an illegal skin trade can devastate a family in places like Eritrea. Suddenly everything from water to firewood to produce must be carried by family members—and often women.
Workers unloading donkeys at the Shinyanga slaughterhouse in Tanzania. Fearing a future in which donkeys go extinct, scientists have found ways to cryopreserve a donkey embryo in liquid nitrogen.
TAHUCHA
One can imagine a time when worldwide donkey populations may dwindle to the point that they would need to be restored. That includes their genetic variability too. That’s where the frozen embryos may come in handy. We may be able to use them to increase the genetic variability of donkeys, which will be especially important if they get closer to extinction, Gambini says. His team had already created frozen embryos for horses and zebras, an idea similar to a seed bank. “We call this concept the Frozen Zoo.”
Creating donkey embryos proved much harder than those of zebras and horses. To improve chances of fertilization, Gambini used the intracytoplasmic sperm injection or ICSI, in which he employed a tiny needle called a micropipette to inject a donkey sperm into an egg. That was a step above the traditional IVF method, in which the egg and a sperm are left floating in a test tube together. The injection took, but during the incubating week, one after the other, the embryos stopped dividing. Finally, on day seven, Gambini finally spotted the exact sight he was hoping to see. One of the embryos developed into a burgeoning ball of cells.
“That stage is called a blastocyst,” Gambini says. The clump of cells had a lot of fluids mixed within them, which indicated that they were finally developing into a viable embryo. “When we see a blastocyst, we know we can transfer that into a female.” He was so excited he immediately called all his collaborators to tell them the good news, which they later published in the journal of Theriogenology.
The one and only embryo to reach that stage, the blastocyst was cryopreserved in liquid nitrogen. The team is waiting for the next breeding season to see if a female donkey may carry it to term and give birth to a healthy foal. Gambini’s team is hoping to polish the process and create more embryos. “It’s our weapon in the conservation ass-enal,” he says.
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.
Too much of this ingredient leads to autoimmune diseases, new research shows. Here's how to cut back.
For more than a century, doctors have warned that too much salt in your diet can lead to high blood pressure, heart disease and stroke - and many of the reasons for these effects are well known. But recently scientists have been looking deeper, into the cellular level, and they are finding additional reasons to minimize sodium intake; it is bad for immune cells, creating patterns of gene expression and activity seen in a variety of autoimmune diseases such as multiple sclerosis, lupus, rheumatoid arthritis, and type-1 diabetes.
Salt is a major part of the ocean from which life evolved on this planet. We carry that legacy in our blood, which tastes salty. It is an important element for conducting electrical signals along nerves and balancing water and metabolites transported throughout our bodies. We need to consume about 500 milligrams of salt each day to maintain these functions, more with exercise and heavy sweating as that is a major way the body loses salt. The problem is that most Americans eating a modern western diet consume about 3400 milligrams, 1.5 teaspoons per day.
Evidence has been accumulating over the last few years that elevated levels of sodium can be harmful to at least some types of immune cells. The first signal came in monocytes, which are immune cells that travel to various tissues in the body, where some of them turn into macrophages, a subset of white blood cells that can directly kill microorganisms and make chemical signals that bring other types of immune cells into play.
Two years ago, Dominik N. Müller from the Max-Delbrueck-Center in Berlin, Germany and Markus Kleinewietfeld, an immunologist at Hasselt University in Belgium, ran a study where they fed people pizza and then measured their immune cell function. “We saw that in any monocytes, metabolic function was down, even after a single salty meal,” Kleinewietfeld says. It seemed to be the cellular equivalent of the sluggish feeling we get after eating too much. The cells were able to recover but more research is needed to answer questions about what dose of sodium causes impairment, how long the damage lasts, and whether there is a cumulative effect of salt toxicity.
Kleinewietfeld and his colleagues have hypothesized that too much salt could be a significant factor in the increased number of autoimmune diseases and allergies over the last few generations.
The latest series of experiments focused on a type of T cell called T regulatory cells, or Tregs. Most T cells release inflammatory mediators to fight pathogens and, once that job is done, Tregs come along to calm down their hyperactive brethren. Failure to do so can result in continued inflammation and possibly autoimmune diseases.
In the lab, Kleinewietfeld and his large team of international collaborators saw that high levels of sodium had a huge effect on Tregs, upregulating 1250 genes and downregulating an additional 1380 genes so that they looked similar to patterns of gene expression seen in autoimmune diseases.
Digging deeper, they found that sodium affected mitochondria, the tiny organelles inside of cells that produce much of its energy. The sodium was interfering with how the mitochondria use oxygen, which resulted in increased levels of an unstable form of oxygen that can damage cell function. The researchers injected those damaged Tregs into mice and found that they impaired the animals' immune function, allowing the inflammation to continue rather than shutting it down.
That finding dovetailed nicely with a 2019 paper in Nature from Navdeep Chandel's lab at Northwestern University, which showed in mice that inhibiting the mitochondrial use of oxygen reduced the ability of Tregs to regulate other T cells. “Mitochondria were controlling directly the immunosuppressive program, they were this master regulator tuning the right amount of genes to give you proper immunosuppression,” Chandel said. “And if you lose that function, then you get autoimmunity.”
Kleinewietfeld's team studied the Treg cells of humans and found that sodium can similarly decrease mitochondrial use of oxygen and immunosuppressive activity. “I would have never predicted that myself,” Chandel says, but now researchers can look at the mitochondria of patients with autoimmune disease and see if their gene expression also changes under high salt conditions. He sees the link between the patterns of gene expression in Tregs generated by high salt exposure and those patterns seen in autoimmune diseases, but he is cautious about claiming a causal effect.
Kleinewietfeld and his colleagues have hypothesized that too much salt could be a significant factor in the increased number of autoimmune diseases and allergies over the last few generations. He says a high salt diet could also have an indirect effect on immune function through the way it affects the gut microbiome and the molecules made by microbes when they break down food. But the research results are too preliminary to say that for sure, much less parse out the role of salt compared with other possible factors. “It is still an exciting journey to try to understand this field,” he says.
Additionally, it is difficult to say precisely how this research in animals and human cell cultures will translate into a whole human body. Individual differences in genetics can affect how the body absorbs, transports, and gets rid of sodium, such that some people are more sensitive to salt than are others.
So how should people apply these research findings to daily life?
Salt is obvious when we sprinkle it on at the table or eat tasty things like potato chips, but we may be unaware of sodium hidden in packaged foods. That's because salt is an easy and cheap way to boost the flavor of foods. And if we do read the labeled salt content on a package, we focus on the number for a single serving, but then eat more than that.
Last September, the U.S. Food and Drug Administration (FDA) began a process to update labels on the content of food, including what is meant by the word “healthy” and how food manufacturers can use the term. Many in the food industry are resisting those proposed changes.
Chandel cautions against trying to counter the effects of salt by reaching for foods or supplements full of antioxidants, which, in theory, could reduce the harmful effects on mitochondria caused by a heavy hand with the salt shaker.
Until labels are updated, it would be prudent to try to reduce sodium intake by cutting down on packaged foods while making your own food at home, where you know just how much salt has been added. The Mayo Clinic offers guidance on how to become more aware of the sodium in your diet and eat less of it.
Chandel thinks many people will struggle with minimizing salt in their diets. It’s similar to the challenge of eating less sugar, in that the body craves both, and it is difficult to fight that. He cautions against trying to counter the effects of salt by reaching for foods or supplements full of antioxidants, which, in theory, could reduce the harmful effects on mitochondria caused by a heavy hand with the salt shaker. “Dietary antioxidants have failed in just about every clinical trial, yet the public continues to take them,” Chandel says. But he is optimistic that research will lead us to a better understanding of how Tregs function, and uncover new targets for treating autoimmune diseases.