Was this shared so they could show what their lab does and doesn't do?
"We do research that involves only the lower-levels of the biosafety risk level (BSL-1 and BSL-2) and we do not handle pathogens that can infect humans. All of the lab work is performed by human scientists"
Claude has discovered a previously unknown enzyme system hidden in the DNA of bacteriophages. Beside the enzyme’s gene sits a long array of repeating DNA—a structure that looks somewhat similar to CRISPR.
We don’t yet understand what this system does, but only a handful of known systems share its features, and all of them are able to cut, copy, and paste DNA. Historically, the discovery of such programmable systems has helped revolutionize medicine. CRISPR, for instance, is now the foundation of genetic medicines. But it will take much more work to learn what this system does, and whether it can be put to similar use.
Read more: anthropic.com/news/claude-di…
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Useful to consider what does hold us back in our systems today and what potential we have.
"Thus, no doing, no learning. The first approved product is rarely the safest or the best but when we fail to approve the first we don’t get the much better 5th." - marginalrevolution.com/margi…
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Another huge medical achievement from our very own @UHN 🇨🇦🔥
A Toronto man lived with HIV for 27 years. Then he got leukemia and that diagnosis may have just cured him of both.
His doctors found a bone marrow donor carrying CCR5-Δ32, a rare mutation in ~1% of people of European descent. HIV hijacks immune cells through the CCR5 receptor. If you don't have it, the virus has no door.
The transplant replaced his entire immune system with one HIV can't infect.
He stopped antiretroviral therapy in July 2025. As of today, HIV is undetectable by the most sensitive assays available. No viral reservoir. No immune response to HIV. Nine months clean.
He would be the 11th person in history to possibly be cured of HIV.
HIV cure is possible. We just proved it again at @UHN
Proud of the team at @UHN and @UofT !
Source: uhn.ca/corporate/News/PressR…
Phil Rees retweeted
I sequenced my genome at home, on my kitchen table.
I wrote up exactly how I did it - the equipment, protocol, theory, and cost:
iwantosequencemygenomeathome…
How many years did that take? As of today the scaling laws are still holding and expected to continue. For how long? It's the rate of change that is impressive and hard to understand.
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This is fascinating. If agents were people it might look similar
"They avoided difficult tasks and made small, safe changes instead. No agent took responsibility for hard problems or end-to-end implementation. This lead to work churning for long periods of time without progress"
We built a browser with GPT-5.2 in Cursor. It ran uninterrupted for one week.
It's 3M+ lines of code across thousands of files. The rendering engine is from-scratch in Rust with HTML parsing, CSS cascade, layout, text shaping, paint, and a custom JS VM.
It *kind of* works! It still has issues and is of course very far from Webkit/Chromium parity, but we were astonished that simple websites render quickly and largely correctly.
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This is far from the first. But stepping back, we certainly are in a new place today, compared to 10-20 yrs ago, with the large tech companies contributing directly to advancements to biology, human disease research. We've finally got the tools, and incentives aligned
Today in Cell, we published new research showing how AI can help accelerate cancer discovery. With GigaTIME, we can now simulate spatial proteomics from routine pathology slides, enabling population-scale analysis of tumor microenvironments across dozens of cancer types and hundreds of subtypes.
Developed in partnership with Providence and the University of Washington, our hope is that this work helps scientists move faster from data to insight, revealing new links between genetic mutations, immune activity, and clinical outcomes, and ultimately improving health for people everywhere.
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Phil Rees retweeted
Over the past week, @arcinstitute published three new discoveries that I’m very proud of.
• The world's first functional AI-generated genomes. Using Evo 2 (the largest biology ML model ever trained, which Arc released in partnership with @nvidia in February), Arc scientists took advantage of the fact that Evo 2 is a generative model to produce completely new sequences for complete phage genomes. That is, they used AI to produce wholly new, never-before-seen-by-nature genomes. They experimentally synthesized these genomes and showed that these AI-generated phages actually work, killing E. coli bacteria with high efficacy.
• Germinal, an AI system for creating new antibodies. Antibody design is one of the great problems of medical biology given their obvious importance and usefulness for creating therapeutics. (Antibodies are tiny particles that help the immune system identify pathogens and other harmful intruders. See also the recent Works in Progress article on this topic: [1].) Today, designing effective antibodies is very expensive and slow. Germinal is a cheap and fast way to produce drug candidates, with success rates of up to 22%. This means that one can go from having to screen thousands of candidates in the lab to screening perhaps a few dozen. It's early, but I suspect that better methods for designing antibodies will be a very big deal for disease treatment in the coming years.
• Today, we published a paper showing that “bridge editing”, which Arc scientists first introduced last year, can make precise edits in human cells that are up to 1 million base pairs long, and without relying on intrinsically unpredictable cellular repair machinery (which CRISPR requires, often leading to editing mistakes). They showed that it’s possible to use this editing to cut out the DNA repeats that cause Friedreich’s ataxia (a neurological disease), an approach which should also be relevant to Huntington’s and other similar disorders. One particularly cool thing about it is that it’s possible to specify every nucleotide within the extended editing window, meaning that recursive bridge edits could potentially be a powerful way to reprogram even biological traits that are caused by many genetic mutations. (Genetic therapies today target single mutations.)
Arc is pretty new. Its doors opened in mid 2022, and it's now 300 people. I’m excited about these discoveries because they show that a number of our hopes in starting Arc are starting to pay off:
• AI/ML and computation are at the center of all three. That is obviously true for the first two, but the mobile genetic element behind bridge editing was also discovered as a result of a complex computational search. One of our premises in starting Arc was the belief that the intersection of software/AI and experimental wet lab biology should enable great things. (And besides requiring great computational work, all three of these also required strong wet lab work, tightly coordinated under a single physical roof.)
• We’ve been toying with the idea that a handful of technologies are enabling a new kind of “Turing loop” in biology: sequencing advances (including single-cell sequencing) give us new ways to read; transformers and AI gives us new ways to think; and functional genomics (such as bridge editing) give us new ways to ways to write. This trio of discoveries span each part of this loop, and we’re hopeful that there’ll be compounding returns in improving each part.
• Arc is a non-profit, which we hoped would make collaborating with others easier, since we can avoid worries about financial return. This is indeed proving important, and all three of these projects involved close partnership with others. Germinal was done in partnership with @SynBioGaoLab at Stanford; Evo 2 was trained in partnership with Nvidia. Bridge editing was jointly published with a structure from the @HNisimasu Lab at the University of Tokyo. Arc tries to make its discoveries useful (see the Evo 2 Designer[2]) for others, and the code behind the computational projects is open source, hopefully making it easy for others to spot new opportunities for collaboration and partnership in the future. Most of all, Arc itself is an ongoing collaboration with @UCSF, @UCBerkeley, and @Stanford.
• With Arc, we wanted to enable better bottom-up and top-down work. With the fully flexible, no-strings-attached funding that we provide to investigators, we want to enable completely unexpected discoveries and avenues of investigation. With our institute initiatives (around creating a virtual cell and curing Alzheimer’s), we want to bring to bear a scale and level of coordination that’s usually difficult in basic science. Germinal is a “surprise” discovery that didn’t involve top-down coordination, whereas Evo 2 is the result of ambitious high-level planning and funding.
• Humanity has never cured a complex disease (a category that includes most neurodegenerative diseases, most cancers, and most autoimmune diseases), and my hope is that Arc can help change this. It’s also clear that AI will revolutionize biology, and I hope that Arc can effectively aggregate the ingredients needed to fully capitalize on its promise. I’m biased, but I think some of the coolest biology in the world is currently being done at Arc. (They’re always hiring if you’re interested.)
While I’m a cofounder of Arc, I spend almost all my time on Stripe, where we spend our time building economic infrastructure for the internet. All credit for Arc’s progress should go to the remarkable scientists and staff who’ve made Arc their home or who’ve chosen to collaborate with us. (You can read more about these particular discoveries in these threads: [3], [4], [5].) I’m also very grateful to the amazing Stripe employees who’ve built the company that makes Arc’s ongoing work possible, and to the millions of customers who’ve chosen to partner with Stripe. John and I feel fortunate to be able to support Arc’s work to the extent that we do.
Maybe this is reading too much into it, but I sometimes feel that there’s a commonality between @arcinstitute and @stripe. Both biology and economic infrastructure involve reasoning about complex systems with many levels of emergent effects, and in both cases building the right tools can have almost unboundedly large benefits. Even though progress in both tends to take a long time, it also feels like the next five years in both will be some of the most interesting in living memory.
(If economic infrastructure is your jam, we have a whole slew of fantastic announcements coming up at Stripe Tour in New York next week. Tune in!)
Phil Rees retweeted
Happy Canada Day!
My beloved country, the true north strong and free.
(image by Radarsat via @csa_asc) asc-csa.gc.ca/eng/multimedia…
Phil Rees retweeted
The ISS silhouetted against the Sun
Photographer Tom Williams has won the *People and Space* category of the 2024 Astronomy Photographer of the Year competition. His image, "High-tech Silhouette," shows a rare moment when the ISS crosses the edge of the Sun. The image was taken in the H-alpha line, which allows the solar structure to be shown in detail. The ISS passed through the frame in just 0.2 seconds, and such transits are extremely rare at one point on Earth.
The image was taken on June 15, 2023, in Trowbridge, UK, after several days of preparation and in perfect weather. Capturing such a shot requires precise orbital calculations, the right technique, and a little luck - cloud cover can ruin all your efforts.
Phil Rees retweeted
Yesterday afternoon I captured a fleeting moment- the moment the ISS transited the moon. Despite being broad daylight, the ISS was clearly visible against the cratered terrain.
I captured it in conjunction with the lunar south pole where astronauts will soon return.
Phil Rees retweeted
.@naval: The things that create knowledge are uniquely influential in the universe. And as far as we know, there are only two systems that create knowledge. There's evolution and there's humans.
But there's a difference even between these two forms of knowledge creation, aren't there? Between evolution and between humans.
@DavidDeutschOxf: Yes, I have argued that the human way of creating knowledge is the ultimate one. That there aren't any more powerful ones than that.
And this is the argument against the supernatural. Assuming that there is a form of knowledge creation that's more powerful than our one is equivalent to invoking the supernatural, which is therefore a bad explanation, as invoking the supernatural always is. The difference between biological evolution and human creative thought is that biological evolution is inherently limited in its range.
And that is because biological evolution has no foresight. It can't see a problem and conjecture a solution. Whenever biological evolution produces a solution to something, it's always before natural selection has even begun.
This is Charles Darwin's insight. This is the difference between Charles Darwin's theory of evolution and the other theories of evolution that had been around for a century or more before that, including Charles Darwin's grandfather and Lamarck. The thing they didn't get is that the creation of knowledge in evolution begins before.
That means that biological evolution can't reach places that are not reachable by successive improvements, that each of which allows a viable organism to exist. Creationists say that biological evolution has in fact reached things that are not reachable by incremental steps, each of which is a viable organism. They're factually mistaken.
But the thing which they have in mind is the idea of a creator who can imagine things that don't exist and who can create an idea that is not the culmination of a whole load of viable things. A thinking being can create something that's a culmination of a whole load of non-viable things. Out of all the billions and billions of species that have ever existed, none of them has ever made a campfire, even though many of them would have been helped by having the genetic capacity to make campfires.
The reason it didn't happen in the biosphere is that there is no such thing as making a partially functional campfire. Whereas there is, for example, with making hot water. Bombardier beetles squirt boiling water at their enemies, and you can easily see that just squirting cold water at your enemies is not totally unhelpful.
Then, making it a bit hotter and a bit hotter, squirting boiling water no doubt required many adaptations to make sure the beetle didn't boil itself while it was making this boiling water. That happened because there was a sequence of steps in between, all of which were useful. But with campfires, it's very hard to see how that could happen.
Humans have the explanatory creativity, and once you have that, you can get to the moon, you can cause asteroids which are heading towards the earth to turn around and go away. Perhaps no other planet in the universe has that power, and it has it only because of the presence of explanatory creativity on it.
Phil Rees retweeted
If you're hungry but too lazy to prepare healthy food, you'll consume junk food. If you're hungry for knowledge but too lazy to seek out the truth, you'll consume misinformation.
That we have the technology and knowledge to go and leave the planet but not the collective desire or will.
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To change the status quo, you do need to first have a dream.
To do something that has never been done. Will appear to the average, perhaps even more so experts, as unattainable.
xitter.cf/adamnash/status/184553…
xitter.cf/SpaceX/status/18455075…
SpaceX is now on to its second generation of reusable rocket technology and all of Europe is still just like, oh, well, crap, we never thought it would work in the first place and did NOT plan for this outcome
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