The biggest scientific breakthroughs of the last 25 years—and a few to watch
From decoding the human genome to exploring the universe, science has made huge strides in the 21st century.
While the 21st century has been bumpy, it has also ushered in monumental scientific and technological breakthroughs that have changed our world for the better. Advances in medicine have allowed for the creation of unprecedented genetic cures, fusion power has inched closer to reality, we’ve learned more about the ancient past on Earth, and in astronomy, we have glimpsed at things once thought to be impossible to render, like a black hole.
We’ve pulled together a list of the most exciting discoveries of the past 25 years, along with five tantalizing unresolved mysteries to watch that could be solved in the coming decades.
The discovery and development of CRISPR
Decades ago, scientists observed that some bacteria have a kind of genetic immune system; when viruses attack them, they capture pieces of the invaders’ DNA and insert them into their own genome to better protect against future attacks.
This natural system called CRISPR, which stands for “clustered interspaced short palindromic repeats,” has now been adapted into a gene-editing tool that has revolutionized countless fields, including medicine, biotechnology, and agriculture. It lets scientists cut and paste any piece of DNA, from single base pairs to whole sets of genes. First released in 2012, CRISPR-based gene editing has led to many medical breakthroughs, including the first approved genetic cure for sickle-cell disease and beta-thalassemia (Casgevy) and enabled the birth of “Baby KJ,” a child born free of an otherwise fatal genetic condition. Jennifer Doudna and Emanuelle Charpentier, pioneers of CRISPR, earned a Nobel Prize for the technology in 2020.
“The development I’m most excited about happened this year,” says Doudna, who is the founder of the Innovative Genomics Institute (IGI). Researchers developed and delivered a personalized CRISPR therapy for an infant with an ultra-rare disease in just six months. “It’s a proof of concept that on-demand gene editing for rare diseases is now possible,” she says. “This will change what can be offered to the thousands of children born each year with conditions medicine has never encountered.”
CRISPR is also fueling a boom in climate and architectural biotech, from disease resistant crops to carbon-capturing microbes.
What will the next 25 years bring?
It’s hard not to wonder what scientific advances the next 25 years will bring. How will new technologies—like AI, green energy, or quantum computing—reshape our lives and world by 2050? Nobody knows, but Doudna has a recommendation.
“What strikes me most about the past 25 years is how many breakthroughs trace back to fundamental research that had no obvious practical application at the time,” she says. “CRISPR is a perfect example: my collaborators and I were studying how bacteria fight off viruses and that curiosity-driven work led to a technology now transforming medicine, agriculture, and even approaches to fighting climate change.”
Scientific momentum needs to be sustained, but even in the best conditions, there still will be challenges. “Getting these tools to the people who need them most— that’s the harder problem we’re still solving.”
