How some bacteria are cleaning up our messy water supply

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The diabetes medication metformin has been touted as a miracle drug. Not only does it keep diabetes in check, but it can reduce inflammation, curb cancer, stave off the worst effects of covid, and perhaps even slow the aging process. No wonder it’s so popular. In the US, the number of metformin prescriptions has more than doubled in less than two decades, from 40 million in 2004 to 91 million in 2021.

Worldwide, we consume more than 100 million kilograms of metformin a year.  That’s staggering.

All that metformin enters the body. But it also exits largely unchanged and ends up in our wastewater. The quantities found there are tiny—tens of micrograms per liter—and not likely to harm humans. But even small amounts can affect aquatic organisms that are literally swimming in it. 

Lawrence Wackett, a biochemist at the University of Minnesota, got interested in this issue about a decade ago. Researchers had observed that at some wastewater treatment plants, the amount of metformin entering was much larger than the amount leaving. In 2022, Wackett’s team and two other groups identified the bacteria responsible for metabolizing the drug and sequenced their genomes. But Wackett still wondered which genes were responsible.

Now he knows. This week, he and his colleagues reported that they have identified two genes encoding proteins that can break down metformin. The study was published in the Proceedings of the National Academy of Sciences. These proteins are produced by at least five species of bacteria found in wastewater sludge across three continents. But here’s what struck me: This isn’t a coincidence. These bacteria evolved the ability to metabolize metformin. They saw an opportunity to capitalize on the ubiquity of the drug in their environment, and they seized it. “This happens all the time,” Wackett says. “Microbes adapt to the chemicals that we make.”

Here’s another example. In the 1960s, farmers began using a new weed killer called atrazine. For about a decade, scientists reported that the chemical appeared to degrade slowly in soil. But about a decade later, that changed. “Everybody was reporting, ‘No, it’s going away really fast—in weeks or a month.” That’s because bacteria evolved the capacity to metabolize atrazine to extract nitrogen. “There is selective pressure,” Wackett says. “The bacteria that figured out how to get that nitrogen out have a big selective advantage.”

This kind of bacterial evolution shouldn’t come as a surprise. We’ve all heard about how the rampant use of antibiotics in people and livestock is driving an antimicrobial resistance crisis. But for some reason, it never occurred to me that bacteria might be evolving in a way that could help us rather than harm us.

That’s good news. Because we have made a real mess of our water supply.

Let’s take a step back. This problem isn’t new. Scientists first detected pharmaceuticals in water more than 40 years ago. But concern has increased dramatically in the past 20 years. In 2008, the Associated Press reported that drinking water in the US was tainted with a wide variety of medications—everything from antibiotics to antidepressants to sex hormones.

It’s not just medicines. A dizzying number of personal care products also end up in the sewers—coconut shampoos and hydrating body washes and expensive face serums and … well, the list goes on and on. Wastewater treatment facilities were never designed to deal with these so-called micropollutants. “For the first 100 years or so of wastewater treatment, you know, the big thing was to prevent infectious diseases,” Wackett says.

Today, many wastewater treatment plants mix wastewater and air in a tank to form an activated sludge—a process that helps bacteria break down pollutants. This system was originally designed to remove nitrogen, phosphates, and organic matter—not pharmaceuticals. When bacteria in the sludge do metabolize drugs like metformin, it’s a happy accident, not the result of intentional design.

Certain technologies that rely on bacteria can do a better job of getting rid of these tiny pollutants. For example, membrane biological reactors combine activated sludge with microfiltration, while biofilm reactors rely on bacteria grown on the surface of membranes. There are even anaerobic “sludge blankets” (worst name ever), in which microbes convert contaminants to biogas in an oxygen-poor environment. But these technologies are expensive, and treatment facilities aren’t required to ensure that treated water is free of these contaminants. At least not in the US.

The European Commission is on its way to adopting new rules stipulating that by 2045, larger wastewater treatment facilities will have to remove a whole host of micropollutants. And in this case, the polluters—pharmaceutical and cosmetics companies—will pay 80% of the cost. The pharmaceutical industry is not a fan of this idea. Trade groups say the new rules will likely result in drug shortages.  

In the US, the federal government is still trying to figure out how to deal with these pollutants. It’s tricky, because it’s not entirely clear what impact small quantities of pharmaceuticals in water will have on the environment and human health. And the risk varies depending on the medication in question. Some pose a clear threat. Oral contraceptives, for example, have caused fertility issues and sex switching in fish. 

Could bacteria save us from estrogen too? Maybe. More than 100 estrogen-degrading microbes have been identified. We just need to find a way to harness them.


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Read more from MIT Technology Review’s archive

In a 2023 issue of The Checkup, my colleague Jessica Hamzelou introduced us to the scientists who study the exposome—all the chemicals we eat, drink, inhale, and digest. Here’s the story.

Hamzelou also wrote about another pervasive pollutant: microplastics. They’re everywhere, and we still don’t really understand what they’re doing to us.  

Microbes aren’t just for cleaning up wastewater. They can also help break down food. And some companies hope to build anaerobic digesters to help them do just that, reported Casey Crownhart last year.

Saima Sidik dove into the fascinating history of how MIT’s innovations in wastewater treatment helped stop the spread of infectious diseases. 

From around the web

Long read: Jane Burns has devoted her life to solving the mystery of Kawasaki disease, a lethal childhood illness that comes on without warning. Now Burns and her oddball team of collaborators have the tools they need to pinpoint the cause.  (NYT)

Older adults should get another covid booster this spring, according to new CDC recommendations. (Washington Post)

Public health officials are “flummoxed” about the Florida surgeon general’s lackluster response to a measles outbreak in the state. (NPR)

After decades of little innovation, biotech finally has a bevy of new drug candidates to treat psychiatric illnesses. “This is a renaissance in neuroscience.” (Stat)

The weird way Alabama’s embryo ruling takes on artificial wombs

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

A ruling by the Alabama Supreme Court last week that frozen embryos stored in labs count as children is sending “shock waves” through the fertility industry and stoking fears that in vitro fertilization is getting swept up into the abortion debate.

The New York Times reports that one clinic, at the University of Alabama, has stopped fertilizing eggs in its laboratory, fearing potential criminal prosecution.

Fertility centers create millions of embryos a year. Some are frozen and others used in research, but most are intended to be transplanted into patients’ wombs so they can get pregnant. 

The Alabama legal ruling is clearly animated by religion—there are lots of Bible quotes and references to “murder” when discussing abortion. But what hasn’t gotten as much notice is the court’s specific argument that an embryo is a child “regardless of its location.” This could have implications for future technologies in development, such as artificial wombs or synthetic embryos made from stem cells. 

The case arose from an incident at an Alabama IVF clinic, the Center for Reproductive Medicine, in which a patient wandered into a storage area and removed a container of embryos from liquid nitrogen. 

That’s when “the subzero temperatures at which the embryos had been stored freeze-burned the patient’s hand, causing the patient to drop the embryos on the floor,” the decision recounts. The embryos, consisting of just a few cells, thawed out and died.

Angered by the mishap, some families then tried to collect financial damages. They sued under Alabama’s Wrongful Death of a Minor statute, which was first written in 1872, long before test-tube babies.

The question the court felt it had to decide: Do frozen embryos count as minor children or not? 

The defendants argued, in part, that an IVF embryo can’t be a child or a person because it’s not yet in a biological womb. No womb, no baby, no birth, and no child. And this is where things start to get interesting and spiral into science fiction territory. 

Justice Jay Mitchell, writing for the majority, pounced on what he called the “latent implication” of the defense’s argument. What about a baby growing to term an artificial womb? Would it also not count as a person, he asked, just because it’s not “in utero”?

According to their ruling, the wrongful-death act “applies to all unborn children, regardless of their location,” and “no exception” can be made for embryos regardless of their age, even if they’ve been in deep freeze for a decade. Nor does the law exclude any type of “extrauterine children” science can conceive.

It’s common for judges to wrestle with complex questions as they try to apply old laws to new technology. But what’s so unusual about this decision is that the judges ended up ruling on technology that hasn’t been fully invented.

“I think the opinion is really extraordinary,” says Susan Wolf, a professor of law and medicine at the University of Minnesota. “I can’t think of another case where a court powered its ruling by looking not only at technology not actually before the court, but number two, that doesn’t exist in human beings. They can’t make a binding decision about future technology that is not even part of the case.” 

Bad law or not, the question the Alabama justices ruled on could soon be a real one. Several companies are actually developing artificial wombs to keep very premature infants alive, and other research labs are working with fluid-filled bottles in which they’ve grown mouse embryos until they are fetuses with beating hearts. 

One startup company in Israel, Renewal Bio, says it wants to grow synthetic human embryos (the kind formed by stem cells) until they are 40 days old, or more, in order to collect their tissue for transplant medicine. 

All this technology is racing along, so the question of the moral and legal rights of incubated human fetuses might not be hypothetical for very long. 

Among the dilemmas lawyers and doctors could face: If a fetus is growing in a tank, would a decision to shut off its support systems be protected under liberal states’ abortion laws, which are typically based on the rights of a pregnant person? Would a fetus engineered solely to grow organs, lacking a brain cortex and without sentience, also still be considered a child in Alabama?

So while it’s obvious that the Alabama decision reflects the justices’ religious views rather than science, and that it could hurt people who just want to have a baby, maybe it is time to think about what the court calls the “many difficult questions” the wrongful-death case has raised about “the ethical status of extrauterine children.”


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For the first time, you can easily order GMOs to plant at home. The biotech plants on sale include a bright-purple tomato and a petunia plant that glows in the dark. (MIT Technology Review)

From MIT Technology Review’s archives

Last fall, my colleague Cassandra Willyard told us everything we need to know about artificial wombs. The experimental devices, she explained, are being developed to give premature babies more time to develop. So far, they’ve been tested on lambs, but human studies are being planned.

Another kind of artificial womb is used to keep very early embryos developing longer in the lab. A startup based in Israel called Renewal Bio says it hopes to grow “synthetic” human embryos this way longer than ever before as a way of bio-printing organs. 

After the US Supreme Court overturned abortion protections in 2022, several American states moved to ban the practice. Anticipating that people may seek abortions anyway, we explained how to end a pregnancy with pills ordered from an online pharmacy. 

Around the web

Elon Musk announced on X that the first volunteer to receive a brain implant from his company Neuralink can control a computer with it and can “move a mouse around the screen just by thinking.” Some commentators are annoyed at Musk for grabbing publicity while revealing few details about the study. (Wired

China is the country with the world’s largest population. It has the most obese people—about 200 million of them. But new weight-loss drugs are in short supply there. (WSJ)

Ready, set, grow: These are the biotech plants you can buy now

This spring I am looking forward to growing some biotech in my backyard for the first time. It’s possible because of startups that have started selling genetically engineered plants directly to consumers, including a bright-purple tomato and a petunia that glows in the dark.

This week, for $73, I ordered both by pressing a few buttons online.

Biotech seeds have been a huge business for a while. In fact, by sheer mass, GMOs are probably the single most significant product of genetic engineering ever. Except most of us aren’t planting rows of cotton or corn that can resist worms or survive a spritz of RoundUp, the big gene-splicing innovations that companies like Monsanto and Pioneer Hi-Bred first introduced in the 1990s.

What makes these new plants different is that you can buy them directly from their creators and then plant them in the yard, on a balcony, or just in a pot. 

caprese salad in a bowl made with halved yellow, red and purple-fleshed cherry tomatoes
Purple tomatoes developed by Norfolk Health Produce.
NORFOLK HEALTHY PRODUCE

Purple tomato

Starting off my biotech shopping spree, I first spent $20 to order 10 tomato seeds from Norfolk Health Produce, a small company in Davis, California, that created what it calls the Purple Tomato. The seeds have a gene introduced from a snapdragon flower, which adds a nutrient, anthocyanin, that also gives the fruits their striking color.

According to Channa S. Prakash, a geneticist and dean at Tuskegee University, the tomato is the “the first-of-its kind GMO food crop marketed directly to home gardeners.”   

The CEO of the company, Nathan Pumplin, was packing seeds when I reached him by phone. He claimed that anthocyanin has health benefits—it’s an antioxidant—but he agreed that the color is a useful sales pitch.

“I don’t need to make a label that says this red tomato is better for you than the other red tomato,” says Pumplin. “We can simply put out the purple tomato, and people say, ‘Oh my gosh, this tomato is purple.’ Its beauty is a distinguishing characteristic that people can just immediately see and understand.”

There is a plan to mass-produce the purple tomatoes for sale in supermarkets. But Pumplin says the company couldn’t ignore thousands of requests from regular gardeners. “It’s not the main focus of our business, but we are very interested in having people grow these at home,” he says. And “if home gardeners want to save the seed and replant it in their gardens for their own use, that is okay.”

couple in their glowing garden of gmo petunias
A promotional video for Light Bio’s firefly petunia.
LIGHT BIO

Glowing flower

I next decided to shell out for the “firefly petunia,” so called because the plant is supposed to glow in the dark. It’s sold by Light Bio, a startup backed by the venture capital firm NFX .

The plant is such a novelty that it’s being sold in a preorder, with promises they will arrive by May. One petunia plant costs $29 plus $24 for shipping. The company’s marketing promises that your plant will unveil “mesmerizing luminescence after dusk” and that “its soothing light is produced from living energy, cultivating a deeper connection with the inner life of the plant.” 

Finally, “Your nurturing care will be rewarded with even greater brilliance.”

It joins a short list of ornamental plants with gene modifications. Another is an orange petunia, approved in the US in 2021, that got its unusual color from a corn gene. (When some copies got loose prior to approval, officials in the US and Europe demanded its eradication in what became known as “the petunia carnage.”) 

Karen Sarkisyan, a synthetic biologist at the MRC Laboratory of Medical Sciences in the UK, is one of the petunia’s creators, and also the chief scientist of Light Bio. His lab is interested in using bioluminescence as a reporter system—a plant could reveal, for instance, how it responds to a toxin or viral infection in lab experiments. 

“In general, we’re trying to make useful things, so this is more of an exception,” he says of the firefly petunia. “The motivation was more about merging biology and art, rather than utility.”

Like a lot of things in biotech, making a glowing petunia was not easy to do—it’s the seemingly sudden result of decades of research into the chemistry that permits certain plants and animals to glow faintly.

Imposing those genetic circuits on plants did not work too well at first. Several years ago, for instance, a Kickstarter project that raised nearly $500,000 to make glowing roses failed to deliver on its promises after the project proved too difficult.

 “It was fairly obvious … that there was no good technology at that time,” says Sarkisyan, who later played a role in discovering genes from a glowing fungus which, after being added to a petunia, made it shine brightly enough to work as a novelty item.

That work continues. Sarkisyan says the company is working on “increasing the brightness and making more colors.” It’s also working on making other types of plants glow, although which ones remain a secret. “I cannot really comment on specific species we’re working on,” he says, although he did show me a photo of a spectacular glowing chrysanthemum.

side view of a genetically modified glowing plant at night
Plants made by Light Bio.
LIGHT BIO

Sarkisyan told me he sometimes likes to relax among the glowing plants and have a meditative experience. Ironically, he can only do that in the lab and not at home, since he lives in the UK. The country, which takes a stricter view on GMOs, has not approved the plants for sale (neither has Europe).

But he thinks the petunia could win over critics. “Especially with all the talk and concerns about the GM stuff, this is the first time there can be a safe, friendly, pleasant GM house plant in every home,” he says. “We think it’s a very interesting project because it is one of the first in consumer biotech. I do think we will see more and more in the future.”

My tomato seeds and glowing petunia haven’t arrived in the mail yet, and there’s still snow where I am. But come spring, I hope to be putting my first biotech crop in the ground. 

Uruguay wants to use gene drives to eradicate devastating screwworms

On a warm, sunny day in Montevideo, Uruguay, the air is smogless and crisp. Inside a highly secured facility at the National Institute of Agricultural Research (INIA) are a sophisticated gene gun, giant microscopes, and tens of thousands of gene-edited flies, their bright blue wings fluttering against the walls of their small, white, netted cages.

These flies—shown to me on video by an INIA veterinarian, Alejo Menchaca—are a new weapon that may soon be unleashed against an enemy that kills cattle and costs the livestock industry millions of dollars every year: the New World screwworm, a parasite common in parts of South America and the Caribbean. 

When a female screwworm fly attacks cattle, it lays eggs, which hatch and turn into worm-like larvae that screw down into the host animal, feeding on flesh along their way and damaging the animal’s skin. Left untreated, the animals eventually die in excruciating agony. 

But Menchaca and colleagues have a plan. Using the genome-editing system CRISPR, they’ve developed what’s known as a gene drive, a type of genetic element that manipulates the reproductive process to spread farther and faster than an ordinary gene. They are about to move into the next stage of caged trials in the lab, with a view to eventually using the genetic tool to decimate the screwworm fly population. They have received a $450,000 grant from the Inter-American Development Bank (IDB) for the research.

“With gene drives, we can control these pests in precise and effective ways,” says Menchaca.

The scientific team in Uruguay poses in a lab.

COURTESY OF ALEJO MENCHACA

Gene drives occur naturally in the wild, but the technology for making them deliberately is new and still pretty controversial. CRISPR allows scientists to cut specific genes in any organism’s DNA and replace them with new sequences. It can be used to tweak an animal’s DNA in a way that affects the species’ survival, often by making the females sterile, when it spreads in the population through breeding. 

Some organizations have been trying to develop gene drives to eradicate mosquitoes. Target Malaria, supported by the Seattle-based Bill & Melinda Gates Foundation (BMGF), is currently the most advanced gene-drive project in the world. But even then, they have never gone beyond caged trials. The process of getting permission for field release efforts has crawled.    

In 2020, the INIA researchers received permission from the Uruguayan government to test their techniques through the country’s existing National Program for Control of Screwworms. Right now, they’re experimenting with different components of the gene drive in gene-edited screwworm flies in the lab. The plan is to create a population of male screwworms with edited versions of genes that are essential for fertility in the female screwworms. When the engineered males are released into the wild, they should mate with females and pass on that gene.

Over successive generations, more and more female screwworms will inherit copies of the gene drive and become sterile, causing a population crash. 

“The thing that’s attractive is if you knock a gene drive into the female, you could disrupt female development,” says Maxwell Scott, an entomologist at North Carolina State University who is working with the Uruguayan team. “It’s potentially a very efficient system.”

The situation is urgent. In July of last year, Panama declared a state of animal health emergency amid outbreaks of cattle screwworm throughout the country. And this February, more than 200 cases of screwworm attacks on animals were reported in Costa Rica, prompting the government to declare an emergency as well. In Uruguay, screwworm flies cost the livestock industry $40 million to $154 million a year. Agricultural export is the linchpin of Uruguay’s economy—over 80% of the goods the nation exports are agricultural products. Beef, which accounts for 20% of that, is worth $2.5 billion a year. 

That makes the country’s search for new tools to combat the pests even more critical, says Carmine Paolo De Salvo, a rural development expert at the IDB. “The [Uruguayan] government is under constant pressure to do something about it,” he says.

Scientists have been trying to tackle screwworms for decades. One method, known as the sterile insect technique (SIT), was developed by researchers at the US Department of Agriculture in the 1950s. SIT involves sterilizing male screwworm flies with radiation. Then, using airplanes, the DNA-damaged males are dropped on the area of infestation. When they mate with wild female flies, the eggs that are produced do not hatch, slowing population growth and preventing the spread of the parasite.

That approach has worked in many countries, including parts of Central America, freeing livestock and wildlife by the millions from the painful grip of the pests. In the US, an area-wide eradication program using SIT worked so well that in 1966, the USDA declared screwworm eradicated within the nation’s borders. The benefits to the livestock industry were immense: producers saved up to $900 million, and the health of both wild and farm animals improved. 

Even with sterile males, eradicating screwworms remains a stubborn challenge, however. To prevent the screwworms from returning, the US—along with Central and South American countries—still runs a permanent barrier zone of sterile flies on the Panama-Colombia border, requiring a continuous supply of billions of flies every year. This effort is too expensive, and it’s simply not powerful enough to eradicate screwworm in South America, where the pests are firmly established and difficult to surveil, researchers say. So the search has been on for alternative tools.

Screwworm flies are seen in a laboratory.

COURTESY OF ALEJO MENCHACA

It was Kevin Esvelt, a pioneering leader in CRISPR gene-drive systems, who first turned the team on to the idea of using one. Esvelt had been experimenting with engineering localized versions of gene drives to target Lyme disease in the US when he met the team of Uruguayan researchers on a tour of the MIT Media Lab. Shortly after that meeting, Esvelt was on a plane to Uruguay, where he met Menchaca and convinced Uruguayan officials to initiate a gene drive project to eradicate screwworms. This would have the advantage over SIT because while SIT reduces the number of successful births, the infertility conferred by the gene drive passes through multiple generations.

The team is looking to use an approach that Scott has successfully developed for livestock pests. In a recent study, Scott and his team tested it on the spotted-wing drosophila, an invasive fly that attacks soft-skinned fruit. The gene drive they developed for that study carried an edited version of the so-called doublesex gene, which is essential for the fly’s reproduction. In caged trials, they combined the engineered fly population with a population that didn’t have the gene edits, mimicking a real-world release. They found that the gene drive was copied at a rate of 94% to 99%—beyond the efficiency they had expected. ​“It was the first really efficient-homing gene drive for suppression of an agricultural pest,” says Scott. He hopes that a similar technique will work with screwworms and allow researchers to perform safer tests.

It won’t be a quick process. Assembling the gene-drive system, testing it, and securing approvals for field release could take many years, says Jackson Champer, a researcher at Peking University in Beijing, who is not part of the Uruguayan team. “It’s not an easy task; there have been many failed attempts at gene drives.” 

Menchaca agrees. He says he and his colleagues aim to integrate their system into the flies and validate the technology in two to three years, adding that they hope to seek permission for field testing and will consider inviting companies to participate in scaling up the technology in the future.

However, Esvelt hopes the Uruguayan researchers will one day be able to release and test their altered screwworms in the wild. He believes that Uruguay’s robust regulatory environment makes the country a likely site for such experiments.

“This would be a project run effectively by Uruguayans, for the benefit of Uruguay, and may be offered eventually—if it works well—to a broader array of folks throughout South America,” he says.

The next generation of mRNA vaccines is on its way

This article first appeared in The Checkup, MIT Technology Review’s weekly biotech newsletter. To receive it in your inbox every Thursday, and read articles like this first, sign up here.

Welcome back to The Checkup! Today I want to talk about … mRNA vaccines.

I can hear the collective groan from here, but wait—hear me out! I know you’ve heard a lot about mRNA vaccines, but Japan recently approved a new one for covid. And this one is pretty exciting. Just like the mRNA vaccines you know and love, it delivers the instructions for making the virus’s spike protein. But here’s what makes it novel: it also tells the body how to make more mRNA. Essentially, it provides instructions for making more instructions. It’s self-amplifying.

I’ll wait while your head explodes.

Self-amplifying RNA vaccines (saRNA) offer a couple of important advantages over conventional mRNA vaccines, at least in theory. Because saRNA vaccines come with a built-in photocopier, the dose can be much lower. One team of researchers tested both an mRNA vaccine and an saRNA vaccine in mice and found that they could achieve equivalent levels of protection against influenza with just 1/64th the dose. Second, it’s possible that saRNA vaccines will induce a more durable immune response because the RNA keeps copying itself and  sticks around longer. While mRNA might last a day or two, self-amplifying RNA can persist for a month.

Lest you think that this is just a tweaked version of conventional mRNA, It’s not. “saRNA is a totally different beast,” Anna Blakney, a bioengineer at the University of British Columbia, told Nature. (Blakney was one of our 35 Innovators Under 35 in 2023.)

What makes it a different beast? Conventional mRNA vaccines consist of messenger RNA that carries the genetic code for covid’s spike protein. Once that mRNA enters the body, it gets translated into proteins by the same cellular machinery that translates our own messenger RNA. 

Self-amplifying mRNA vaccines contain a gene that encodes the spike protein as well as viral genes that code for replicase, the enzyme that serves as a photocopier. So one self-amplifying mRNA molecule can produce many more. The idea of a vaccine that copies itself in the body might sound a little, well, unnerving. But there are a few things I should make clear. Although the genes that give these vaccines the ability to self-amplify come from viruses, they don’t encode the information needed to make the virus itself. So saRNA vaccines can’t produce new viruses. And just like mRNA, saRNA degrades quickly in the body. It lasts longer than mRNA, but it doesn’t amplify forever. 

Japan approved the new vaccine, called LUNAR-COV19, in late November on the basis of results from a 16,000-person trial in Vietnam. Last month researchers published results of a head-to-head comparison between LUNAR-COV19 and Comirnaty, the mRNA vaccine from Pfizer-BioNTech. In that 800-person study, vaccinated participants received either five  micrograms of LUNAR-COV19 or 30 micrograms of Comirnaty as a fourth dose booster. Reactions to both shots tended to be mild and resolve quickly. But the self-amplifying mRNA shot did elicit antibodies in a greater percentage of people than Comirnaty. And a month out, antibody levels against Omicron BA.4/5 were higher in people who received LUNAR-COV19. That could be a signal of increased durability.

The company has already filed for approval in Europe. It’s also working on a self-amplifying mRNA vaccine for flu, both seasonal and pandemic. Other companies are exploring the possibility that self-amplifying mRNA might be useful in rare genetic conditions to replace missing proteins. Arcturus, the company that co-developed LUNAR-COV19 with the global biotech CSL, is also developing self-amplifying messenger RNA to treat ornithine transcarbamylase deficiency, a rare and life-threatening genetic disease. It’s an mRNA bonanza that will hopefully lead to better vaccines and new therapies. 

Another thing

Babies and AI learn language in very different ways. The former rely on a relatively small set of experiences. The latter relies on data sets that encompass a trillion words. But this week I wrote about a new study that shows AI can learn language like a baby—at least some aspects of language. The researchers found that a neural network trained on things a single child saw and heard over the course of a year and a half could learn to match words to the objects they represent. Here’s the story. 

Read more from MIT Technology Review’s archive

mRNA vaccines helped tackle covid, but they can help with so much more—malaria, HIV, TB, Zika, even cancer. Jessica Hamzelou wrote about their potential in January, and I followed up with a story after two mRNA researchers won a Nobel Prize. 

Using self-amplifying RNA isn’t the only way to make mRNA vaccines more powerful. Researchers are tweaking them in other ways that might help boost the immune response, writes Anne Trafton

From around the web

Elon Musk says his company Neuralink has implanted a brain chip in a person for the first time. The device is designed to allow people to control external devices like smartphones and computers with their thoughts. (Washington Post)

In August I  wrote about Vertex’s quest to develop a non-opioid pain pill. This week the company announced positive results from phase 3 trials. The company expects to seek regulatory approval in the coming months, and if approved, the drug is likely to become a blockbuster. (Stat)

In some rare cases, it appears that Alzheimer’s can be transmitted from one person to another. That’s the conclusion of a new study: it found that eight people who received growth hormone from the brains of cadavers before the 1980s had sticky beta-amyloid plaques in their brains, a hallmark of the disease. The growth hormone they received also contained these proteins. And when researchers injected these proteins into mice, the mice also developed amyloid plaques. (Science)