How David Liu’s Gene Editing Breakthroughs Are Rewriting the Future of Medicine
A groundbreaking shift is happening in the world of gene editing, and leading the charge is David Liu, an American molecular biologist whose innovative research is redefining the very essence of life with remarkable accuracy. As a professor at the Broad Institute of MIT and Harvard, Liu recently received a Breakthrough Prize in Life Sciences for his development of two game-changing technologies: one that’s already making a difference for patients suffering from severe genetic disorders, and another that’s set to transform medicine in the near future.
In an interview with AFP before the prestigious award ceremony in Los Angeles, Liu shared his insights on this exciting journey.
He’s set to receive a whopping $3 million for his work on “base editing” and “prime editing,” and he plans to give away most of it to support his charitable foundation.
“The ability to change a DNA sequence of our choosing into a new sequence of our choosing is a fundamentally very powerful capability,” the 51-year-old said, foreseeing uses not just in human medicine but areas like developing more nutritious or disease-resistant crops.
-Correcting the code –
DNA consists of four chemical “letters” — the nucleotide bases A, G, T, and C. Changes in this sequence can lead to thousands of human diseases, but until recently, gene editing was only able to address a small fraction of them.
Even CRISPR-Cas9, the revolutionary technology that snagged a Nobel Prize in 2020, has its own set of significant limitations.
It cuts through both strands of the DNA helix, which makes it more effective at disrupting genes rather than fixing them, and this process can sometimes introduce new errors.
“Being able to use genome editing to treat genetic diseases requires, in most cases, ways to correct a DNA misspelling, not simply to disrupt a gene,” Liu said.
That insight inspired his lab to create base editing, a technique that utilizes the Cas9 protein—modified so it can’t cut both strands of DNA—to locate a specific DNA sequence. Then, it employs another enzyme to swap one letter for another, like changing C to T or G to A.
However, reversing that change—from T back to C or A to G—proved to be more challenging. Liu’s team tackled this obstacle by engineering entirely new enzymes.
These base editors are now capable of correcting around 30 percent of the mutations responsible for genetic diseases. The technology is already being tested in at least 14 clinical trials.
In one of these trials, Beam Therapeutics—which Liu co-founded—reported that it successfully treated patients with AATD, a rare genetic disorder that impacts the lungs and liver, using just a single drug infusion.
Unlike traditional gene therapies that often disrupt faulty genes or sidestep them, base editing actually repairs the mutation itself.
“This was the first time that humans have corrected a mutation that causes a genetic disease in a patient,” Liu said.
–Cystic fibrosis hope –
Base editing, often referred to as “CRISPR 2.0,” isn’t a one-size-fits-all solution for every mutation out there. In fact, about 70 percent of the roughly 100,000 known mutations that lead to diseases are still beyond its reach, especially those caused by missing or extra letters in the DNA sequence.
To broaden the options available, Liu’s lab rolled out prime editing in 2019—a technique that can actually replace entire segments of faulty DNA with corrected sequences.
If you think of CRISPR as a pair of scissors that snip DNA, and base editors as a pencil that fixes individual letters, then prime editing is like using a word processor’s “find and replace” feature.
Creating this tool required a series of breakthroughs Liu’s team describes as “small miracles.” The result is, he said, “the most versatile way we know of to edit the human genome.”
Liu and his team have set their sights on some ambitious targets with prime editing, including cystic fibrosis. This common genetic disorder is typically caused by the absence of three DNA letters, leading to a troublesome buildup of thick mucus in the lungs and digestive system.
What’s impressive is that Liu’s lab has made a lot of its research freely available, sharing DNA blueprints through a nonprofit library that tens of thousands of labs around the globe rely on.
“The science we create — which is ultimately funded by society, through governments and donors — ultimately goes back to benefit society.”
This year’s Breakthrough Prize awards arrive at a challenging time for science in the US, as President Donald Trump’s administration cuts funding for key institutions like the National Institutes of Health (NIH).
“The NIH is a treasure, not just for this country but for the world,” said Liu. “Trying to dismantle the heart of what supports science in this country is like burning your seed corn.”
How David Liu’s Gene Editing Breakthroughs Are Rewriting the Future of Medicine
