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Some viruses that infect bacteria have ‘Z-DNA’, which uses a genetic alphabet different from the As, Ts, Cs and Gs in the DNA of nearly all other organisms. Dozens of these bacteriophages (or ‘phages’) write their genomes using a chemical base called 2-aminoadenine, Z for short, instead of adenine. Now, two teams have spelled out how the system works. These phages use specialized enzymes to make genes with an alternative nucleobase. “It represents the first discovery of a ‘shadow biosphere’ since [Carl] Woese identified the Archaea a half century ago,” says synthetic biologist Steven Benner.
The world has reached the milestone of administering one billion doses of COVID-19 vaccines, just four months after the World Health Organization (WHO) authorized the first vaccine for emergency use and roll-outs began in countries such as the United States and the United Kingdom. The speed at which they have been administered is remarkable, but unequal distribution of the vaccinations highlights global disparities. “It is an unprecedented scientific achievement. Nobody could have imagined that, within 16 months of the identification of a new virus, we would have vaccinated one billion people worldwide,” says WHO chief scientist Soumya Swaminathan.
If everything goes to plan, Cuba could be the first Latin American country to develop and manufacture its own vaccine against COVID-19. The candidate, called Soberana 02, entered phase III trials in people in March. The name means ‘sovereign’ — a powerful concept in a country that has been hit hard by geopolitical discord. “We wanted to solely rely on our own capacities to vaccinate our population, not on other people’s decisions,” says vaccine designer Vicente Vérez Bencomo. “And life is proving us right. What we’re seeing across the world is that vaccine supplies are being hoarded by rich countries.”
Reruns of old science-fiction series help pass the time for the lone conscious passenger on a ship full of sleeping crew in the latest short story for Nature’s Futures series. But a catch-phrase turns out to be a passphrase — with humorously disastrous consequences.
In California, low wages, weak labour protections and precarious immigration status are among the reasons that food and agricultural workers had an almost 40% increased risk of dying last year, compared with the risk for the state’s general population. A growing number of public-health researchers are saying it's time to move on from simply identifying the social determinants of health, and start pushing for leaders to address them. “The pandemic has turned up the dial, and to me it brings out a sense of urgency,” says medical geographer Arrianna Marie Planey. “I see a study saying COVID is higher in farmworkers, and I’m not interested — I want to know what’s next.”
Over the past eight months, I’ve witnessed how exploitation, poverty and discrimination drove COVID-19 in California’s San Joaquin Valley. Farmworkers told me that they felt their work was called essential, but their lives were treated as expendable. Scholars have connected these problems to disease over the past 150 years, so I’ve also been asking why so little has changed. Some of the researchers I talked with were frustrated with how scholarship mounts, but the problems aren’t addressed. This piece is about why change is so hard, and what can be done.
Croissants did not accompany French astronaut Thomas Pesquet to the International Space Station, says space scientist Alain Maillet — but lobster, beef bourguignon and almond tarts did. (The New York Times | 10 min read)
I’ll be basking in the liquid sunshine of a British bank holiday on Monday, so there will be no Briefing. The answer will be in Tuesday’s e-mail, all thanks to Briefing photo editor and penguin wrangler Tom Houghton.Your e-mails are always welcome at email@example.com — we read every one.