“This year’s prize is about rewriting the code of life,” said Goran K. Hansson, secretary general of the Royal Swedish Academy of Sciences.

This was the first time two women jointly won a Nobel in chemistry. “I wish that this will provide a positive message, specifically, to young girls who would like to follow the path of science,” Charpentier told reporters Wednesday morning.

“I’m over the moon, I’m in shock, I couldn’t be happier,” Doudna said at a University of California at Berkeley news conference. She said she and Charpentier are “waving to each other across the Atlantic right now.”

Francis Collins, director of the National Institutes of Health, said this prize was a long time coming. The 2012 publication of the scientists’ paper describing CRISPR is one of the most-cited studies in modern science. “Every year we are like: ‘Okay, is this going to be the year?’ ” he said, adding that he was “absolutely thrilled at 5:30 in the morning” to see the Nobel committee recognize the two researchers.

Ancient microorganisms developed the first version of CRISPR as their immune system. Because bacteria use it to slice out foreign genetic material once viruses invade, CRISPR-Cas9 is frequently likened to molecular scissors.

It can hunt for specific sections of DNA and snip those out: The human cell contains about 6 billion chemical units of DNA, called base pairs. CRISPR’s tremendous power is that it can find and cut just one. What’s more, when manipulated by scientists, CRISPR has the flexibility of a word processor — with functions such as find-and-replace, find-and-delete or simply find.

“We can now change the genetic information in any cell in any organism,” said Claes Gustafsson, chairman of the Nobel Committee for Chemistry.

Since its discovery eight years ago, the tool has been widely deployed in research laboratories. It has transformed the patterns of butterfly wings and allowed scientists, for the first time, to mutate ants. It also has been used for plant breeding and is a cutting-edge medical therapy in clinical trials for inherited diseases such as sickle cell disease.

“This is definitely a very expected prize for me,” Luis Echegoyen, president of the American Chemical Society, said in an interview. “It’s going to change the world and how we treat diseases.”

Although gene-editing techniques existed before CRISPR, none were so easy to use or were adopted so rapidly. “If you walk into any lab, including mine at NIH, there’s a very high likelihood that CRISPR-Cas is in the middle of those experiments,” said Collins, whose research uses CRISPR to identify genetic risk factors in diabetes.

It would be difficult to find an NIH grant for molecular biology research that didn’t involve CRISPR, he said. “It’s clearly billions of dollars a year that we’re investing in this.”

NIH-funded research also includes using a CRISPR system to diagnose coronavirus infections, with the goal of swiftly identifying viral genomes in the swirl of genetic material taken from a nasal swab. That has the potential to be a faster and more precise tool than the tests that use a technique called PCR, Collins said.

CRISPR’s great power has also spurred controversy. In 2018, a researcher in China used CRISPR to edit human embryos in an attempt to make them immune from HIV, an approach Doudna and other scientists condemned as reckless and unethical. Those embryos were carried to term, with twin babies. A Chinese court sentenced the scientist, He Jiankui, to three years in prison.

And the tool has sparked a long-running patent battle between two groups that claim ownership, one led by the University of California that includes the two prize winners, and the other by MIT and Harvard’s Broad Institute. A biochemist there, Feng Zhang, pioneered the use of CRISPR in animal and plant cells. Doudna said she did not think the Nobel award would affect the ongoing patent case.

Many scientists also considered Zhang a contender for the Nobel Prize. At Wednesday’s announcement, Gustafsson declined to answer whether the Nobel committee considered other CRISPR researchers for this year’s prize. “It’s a big field, and there’s a lot of good science. … I can only say that,” he said.

Geneticist Eric Lander, director of the Broad Institute, tweeted: “Huge congratulations to Drs. Charpentier and Doudna on the @NobelPrize for their contributions to the amazing science of CRISPR!”

Since 1901, the Nobel Committee has awarded 112 prizes in chemistry to 186 people. Seven, including Doudna and Charpentier, were women. “I’m proud of my gender,” Doudna said. “For many women there’s a feeling that, no matter what they do, their work will never be recognized as it might be if they were a man. I’d like to see that change.”

Last year, John B. Goodenough became the oldest person to win a Nobel — he was 97 — for his work developing lithium-ion batteries, an award he shared with chemists M. Stanley Whittingham and Akira Yoshino.

Charpentier and Doudna split a prize of 10 million Swedish kronor, or about $560,000 each. The University of California at Berkeley also awarded Doudna a free parking space on campus.

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