Renowned biochemist and genomics researcher Jennifer Doudna — half of the team that discovered the revolutionary but controversial genomic editing technology known as CRISPR-Cas9 — has been selected as the recipient of UC San Diego Scripps Institution of Oceanography’s (SIO) 2019 Nierenberg Prize for Science in the Public Interest.
The award presentation and accompanying lecture was held on the Scripps Institution of Oceanography campus Oct. 7.
In 2012, Doudna and collaborator Emmanuelle Charpentier discovered the CRISPR-Cas9 method of genomic editing. They demonstrated that a bacterial protein called Cas9 could be used to cut and edit DNA, allowing scientists to change or remove genes quickly and with extreme precision.
“People had previously recognized if you could introduce a break in a genome — the DNA of a cell — in the desired position, you could trigger a change in the DNA sequence, in just that position and nowhere else,” Doudna explained. “The challenge had been, at that time, how to introduce double-stranded breaks into DNA so this process can take over. There were earlier technologies to do this … but they were difficult enough that most labs weren’t able to adopt them. The wonderful thing about CRISPR is, it’s a simple enough system that scientists immediately grasped how powerful it could be and how it simplified this challenge of making a targeted edit to the genome.”
In her introductory remarks, San Diego Vice Chancellor for Marine Sciences, SIO Director and Dean of the School of Marine Sciences Margaret Leinen said: “(Doudna’s) work in generating a new technology for editing genes has become part of the everyday lexicon of those in the United States. … Innovators like Dr. Doudna serve as an inspiration for the generation of scientists and trailblazers.”
Walter Tschinkle, Nierenberg Prize namesake Bill Nierenberg’s son-in-law and Florida State University professor, called Doudna’s 2012 discovery “one of the most significant discoveries in the history of biology.”
Since 2012, revelations into the ethics and implications of CRISPR-Cas9 have been coming at blazing speeds. As such, Doudna focused half of her talk on the future, opportunities and challenges of this technology.
“I personally think genome editing, at least in the near-term, will have its biggest impact on human society through agriculture applications,” she said. “But this doesn’t come without challenges.”
For example, she said CRISPR has been used to alter the genetics of tomatoes in a way that produces plants with fruits genetically identical to its parent species, except that it makes two or three times more fruit per plant. “Imagine how that might impact water use or the need for various kinds of nutrients or pesticides for these plants,” she posed.
However, Doudna cited a Penn State study that used CRISPR technology to remove the gene in mushrooms that makes them turn brown when cut. “That raised the question of ‘How are products like this going to be regulated?’ or ‘Are they going to be regulated?’ ” she said. “In the United States, the Department of Agriculture decided that modified plants of that type were not going to be regulated … because they didn’t introduce a new piece of foreign DNA into the mushroom, they simply disrupted a natural gene that was there.”
In Europe, there is an active debate about this and whether to regulate such type of plant products.
As another example, she said there was interest in using the technology on mosquito populations that transmit illnesses such as Dengue Fever and Zika: “to control the mosquito populations so they cannot pass along a parasite that would otherwise be spread by mosquito bites could have a dramatic impact on public health.”
Although there is interest in using CRISPR in the bio-medical field, Doudna explained there are two things to consider: “When we talk about genome editing, it’s important to understand there are two types of cells that can be edited: one is Somatic Cell editing, which means making changes to DNA that ultimately effect fully developed organs or organisms (such as humans) and are not inherited by future generations; the other is Germ Cells editing, like sperm or eggs or embryos, which are inherited by future generations.”
Doudna noted there are “very different” issues that come along with these two types of editing. “If we are working on Somatic Cells to cure someone of a genetic disease, I would argue that technology is not different in terms of safety and effectiveness from other kinds of therapies you could use.”
She said this presents “tremendous opportunity” and that “the field is moving really fast” with clinical trials underway for cancer and eye diseases. But, “making a change in someone that becomes permanent in their children and their grandchildren (with Germ Cell editing) is different.”
As such, heritable germline genome editing is creating a little more ethical controversy, with questions arising “very early on” about whether it could be conducted in human embryos, leading to the potential for what she called “CRISPR babies” with custom gene editing such as that for certain hair color or abilities.
“A report was published in early 2017 by the National Academies of Science on this, and called for a moratorium or restraint from using this to create gene-edited babies,” she said.
But at the end of 2018, scientist He Jiankui announced at a conference in Hong Kong that he had created human embryos that had gene edits using CRISPR, which were implanted and resulted in the birth of twin girls.
“This set off international outcry; I think many of us felt this was wrong on many levels,” Doudna said. “The science wasn’t ready for this kind of application, but it was also wrong because there hadn’t been the opportunity to deeply consider whether this would be wise use of this technology.”
Further, she noted, the changes made had not been tested in humans. “It was chilling to me, to see this presented as something desirable to be done. That being said, where do we go from here? Are CRISPR babies right around the corner? There is no doubt there is a lot of interest in this … people want to know how soon it will be possible and how they can get involved.
“You might or might not be relieved to know many of the traits people are looking to alter involve many genes, not just one, and in most cases, we don’t know the collection of genes. So like it or not, we’re probably not going to be able to address (this) any time soon.”
The Nierenberg Prize for Science in the Public Interest has been awarded annually since 2001 by Scripps Oceanography. The prize includes a bronze medal and $25,000. Previous Nierenberg Prize winners include NASA astronaut and administrator Charles Bolden, filmmaker Sir David Attenborough, primatologist Dame Jane Goodall, and filmmaker James Cameron.