Every December, the journal Nature names ten people who helped shape science over the past year. The honorees are usually researchers behind landmark papers or bold new theories. The 2025 edition, released on 8 December, looked different. It included the founder of an AI company, a geoscientist who descended 9,000 meters into the ocean, a public-health official who lost her job less than a month after taking it, and a baby only a few months old when his treatment began. Why did Nature choose them?
A therapy built for one child
KJ Muldoon was born in the United States in 2024 and, soon after birth, was diagnosed with severe CPS1 deficiency, an extremely rare inherited disorder that leaves the body unable to break down the protein in food properly. Without treatment, his chances of survival were poor, and the only established remedy was a liver transplant. The problem was time. A baby has to grow before surgery is possible, and KJ faced a high risk of coma or death before he would be big enough for the operation.
His doctors at Children's Hospital of Philadelphia and Penn Medicine, led by Rebecca Ahrens-Nicklas and Kiran Musunuru, tried something no one had done before: a gene-editing therapy designed around KJ's own mutation. Instead of a conventional CRISPR edit, which cuts DNA, they used base editing, a CRISPR-derived technique that changes a single DNA letter with precision. KJ received his first dose at about six months old, in February 2025, followed by further doses in March and April.
It is still too early to call him cured. But KJ can now eat more foods and move around on his own. His case is a sign that medicine is starting to shift from treatments designed for the average patient toward treatments built for one person.
The founder who changed how AI is shared
In January 2025, the Chinese company DeepSeek released its R1 model and caught the world's attention. It could hold its own against the best AI systems of the day, was far cheaper to train and, most important, was open for anyone to use and build on. In September, R1 also became the first major AI model to go through peer review, with the paper published in Nature itself.
That is why its founder, Liang Wenfeng, made the list. He was recognized not for building the most complex model but for changing how AI is developed and shared. DeepSeek's rise also marked a shift in China's place in the global technology race, from catching up to helping set the direction.