Los Angeles Times

Gene- editing tool earns the Nobel

Biochemist from UC Berkeley shares award for her work on gene- editing tool.

- By Henry Chu and Deborah Netburn

Two women, including UC Berkeley biochemist, share prize for work on the “molecular scissors” of CRISPR.

Two women from different continents who met at a cafe in Puerto Rico were awarded the Nobel Prize in chemistry Wednesday for their pioneering work on CRISPR, a gene- editing tool that gives scientists the power to change the behavior of living cells and potentiall­y cure diseases.

UC Berkeley biochemist Jennifer A. Doudna and Emmanuelle Charpentie­r, director of the Max Planck Unit for the Science of Pathogens in Berlin, harnessed an ancient immune response found in bacteria and other single- celled organisms and shaped it into an elegant pair of “molecular scissors,” the Nobel Committee said. The tool has transforme­d the life sciences in just eight years.

With CRISPR, researcher­s can alter specific sequences on the human genome with the hope of priming patients to f ight cancer or curing diseases such as sickle- cell anemia. It also paves the way for improving plants and livestock by imbuing them with greater disease resistance, and for safer transplant­s of animal organs into humans.

A researcher in China said he used CRISPR to tweak the DNA of human embryos so they would grow up to have immunity to HIV. The controvers­ial work produced three babies and resulted in a three- year prison sentence for the scientist.

“There is enormous power in this genetic tool, which affects us all,” said Claes Gustafsson, chair of the Nobel Committee for Chemistry. “It has not only revolution­ized basic science but also resulted in innovative crops and will lead to groundbrea­king new medical treatments.”

He added that “the enormous power of this technology means that we need to use it with great care. But it’s equally clear that this is a technology and method that will provide humankind with great opportunit­ies.”

Charpentie­r, who was born in France, said she “was very emotional” after learning that she and Doudna had won.

It is the f irst time the prize has been shared by two women.

Charpentie­r said she hoped it would send “a positive message” to girls and young women “who would like to follow the path of science and ... show them that, in principle, women in science can also be awarded prizes but, more importantl­y, that women in science can also have an impact through the research.”

Doudna said she realized early on that the pair were on to something: “You never know where science is heading, but I kind of had a feeling it would be a big deal.” She was right. “The seminal paper they published together has been cited more than 9,500 times — approximat­ely once every eight hours since its publicatio­n in 2012,” said David Liu, a chemical biologist at Harvard University who has worked to perfect the system.

CRISPR is made up of two basic components. The first is a piece of RNA that locates a predetermi­ned sequence of DNA in an organism’s genome that scientists want to alter. The second is a type of protein called an enzyme that attaches itself to the target section of DNA and splices it.

When a DNA strand has been cut, the cell immediatel­y sets to work to repair it. Scientists can exploit this impulse by adding another piece of DNA to the CRISPR complex that the cell can use to mend the break. This makes it possible to insert new genes into a DNA strand.

CRISPR can also be used to disable faulty genes and even change a single letter on a strand of DNA. The system takes advantage of the way bacteria find and destroy invading viruses by storing sequences of viral DNA within their own DNA. Those sequences are bookended by a repeating sequence of letters that give CRISPR its name — Clustered Regularly Interspace­d Short Palindromi­c Repeats. ( The first CRISPR systems discovered were indeed partly palindromi­c; however, scientists later found that this is not universall­y true.)

Doudna and Charpentie­r, who met in 2009 while attending a scientific conference, were not the f irst to spot these odd stretches of DNA, nor were they f irst to realize that it was part of a bacterial immune system. Indeed, by the time they published their revolution­ary paper, other scientists had shown that the system required a piece of RNA and an enzyme.

But the two women were the f irst to identify that another piece of RNA was required to bind the two together and found a way to streamline them. With all the components in place, the system could be programmed to find and cut any piece of DNA a scientist desired, making it a more eff icient genome editor than had ever been seen before.

Within six months, six independen­t research teams had demonstrat­ed that the CRISPR gene editing system would work in animal cells.

Most early CRISPR systems used an enzyme called Cas9 to make the cut. More recently, scientists have been experiment­ing with other enzymes as well.

“My greatest hope is that it’s used for good, to uncover new mysteries in biology and to benefit humankind,” Doudna said.

Last year saw the first attempt in the U. S. to use the CRISPR tool to treat cancer patients. Doctors took immune- system cells from the patients’ blood, altered the DNA inside those cells to help them recognize and f ight cancer, and reintroduc­ed them into the patients. Whether the treatment will improve their chances of survival is still too early to say.

The ability to edit genes is fraught with difficult ethical questions, which Doudna examined in her book “A Crack in Creation: Gene Editing and the Unthinkabl­e Power to Control Evolution.” The book, which she wrote with her former student Samuel H. Sternberg, said that CRISPR technology offered “both the greatest promise and, arguably, the greatest peril for the future of humanity.”

“It’s widely available and it’s accessible to people around the globe,” Doudna told The Times when the book was published in 2017. “That’s what’s wonderful about it, but also one of the real challenges. How do you control something like that?”

The CRISPR breakthrou­gh has spawned a protracted legal f ight with the Broad Institute at MIT over patents for the technology. Other scientists — particular­ly Feng Zhang of the Broad — have conducted significan­t research on the technology, but the U. S. patent office recognized Doudna as the inventor last year and awarded several key patents to UC Berkeley.

Doudna has helped found a number of CRISPRbase­d companies, including Mammoth Bioscience­s, Caribou Bioscience­s, Intellia Therapeuti­cs and Scribe Therapeuti­cs. Charpentie­r is co- founder of CRISPR Therapeuti­cs.

“There comes a point when discoverie­s need to be translated in a way that is difficult or impossible to do in an academic setting,” Doudna said. “It is really exciting to see these companies develop real solutions in biomedicin­e and other areas using CRISPR technology.”

The Nobel Prize in chemistry frequently honors research that leads to practical applicatio­ns in wide use.

The award is one of the six 2020 Nobel Prizes that are being announced through Monday.

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 ?? Photog r aphs by Susan Walsh Associated Press ?? THE NOBEL COMMITTEE said French- born researcher Emmanuelle Charpentie­r, left, and UC Berkeley’s Jennifer A. Doudna harnessed an immune response found in bacteria to create a pair of “molecular scissors.”
Photog r aphs by Susan Walsh Associated Press THE NOBEL COMMITTEE said French- born researcher Emmanuelle Charpentie­r, left, and UC Berkeley’s Jennifer A. Doudna harnessed an immune response found in bacteria to create a pair of “molecular scissors.”

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