CRISPR, 10 Years On: Learning to Rewrite the Code of Life
The gene-editing technology has led to innovations in medicine, evolution and agriculture — and raised profound ethical questions about altering human DNA.
Ten years ago this week, Jennifer Doudna and her colleagues published the results of a test-tube experiment on bacterial genes. When the study came out in the journal Science on June 28, 2012, it did not make headline news. In fact, over the next few weeks, it did not make any news at all.
Looking back, Dr. Doudna wondered if the oversight had something to do with the wonky title she and her colleagues had chosen for the study: “A Programmable Dual RNA-Guided DNA Endonuclease in Adaptive Bacterial Immunity.”
“I suppose if I were writing the paper today, I would have chosen a different title,” Dr. Doudna, a biochemist at the University of California, Berkeley, said in an interview.
Far from an esoteric finding, the discovery pointed to a new method for editing DNA, one that might even make it possible to change human genes.
In just a decade, CRISPR has become one of the most celebrated inventions in modern biology. It is swiftly changing how medical researchers study diseases: Cancer biologists are using the method to discover hidden vulnerabilities of tumor cells. Doctors are using CRISPR to edit genes that cause hereditary diseases.
“The era of human gene editing isn’t coming,” said David Liu, a biologist at Harvard University. “It’s here.”But CRISPR’s influence extends far beyond medicine. Evolutionary biologists are using the technology to study Neanderthal brains and to investigate how our ape ancestors lost their tails. Plant biologists have edited seeds to produce crops with new vitamins or with the ability to withstand diseases. Some of them may reach supermarket shelves in the next few years.
CRISPR has had such a quick impact that Dr. Doudna and her collaborator, Emmanuelle Charpentier of the Max Planck Unit for the Science of Pathogens in Berlin, won the 2020 Nobel Prize for chemistry. The award committee hailed their 2012 study as “an epoch-making experiment.”
Dr. Doudna recognized early on that CRISPR would pose a number of thorny ethical questions, and after a decade of its development, those questions are more urgent than ever.
Will the coming wave of CRISPR-altered crops feed the world and help poor farmers or only enrich agribusiness giants that invest in the technology? Will CRISPR-based medicine improve health for vulnerable people across the world, or come with a million-dollar price tag?
The most profound ethical question about CRISPR is how future generations might use the technology to alter human embryos. This notion was simply a thought experiment until 2018, when He Jiankui, a biophysicist in China, edited a gene in human embryos to confer resistance to H.I.V. Three of the modified embryos were implanted in women in the Chinese city of Shenzen.
