New Challenges May Lie Ahead for Use of CRISPR in Humans

The gene-editing tool CRISPR/Cas9 has garnered much attention over the past few years — and rightly so.

A new paper suggests further research is needed on the body’s immune response to CRISPR gene editing.

Visual: Maciej Frolow/Getty

Using proteins from bacteria, scientists are able to modify genomes by adding, removing, or altering precise sections of DNA, opening the door to potential cures for a variety of genetic defects. This year, the first human clinical trials are set to begin to address two blood disorders — beta thalassemia and sickle-cell disease.

But a paper published last Friday may tamp down some of the excitement.

The study, which was posted on the preprint site bioRxiv and hasn’t yet been peer reviewed, suggests that some patients’ immune systems may be primed to attack the Cas9 proteins used in gene editing, rendering the therapy ineffective or potentially causing negative side effects.

In response to the frenzied reaction, the study’s lead author and other outside researchers clarified that the findings do not constitute a blow to CRISPR — just a factor that should be considered and studied further. Three of the top companies working on human trials — Editas Medicine, CRISPR Therapeutics, and Intellia Therapeutics — described possible workarounds to avoid adverse immune responses, including only using CRISPR to edit cells outside of the body, or exploring other proteins that could be used instead of Cas9.

Also in the news:

• The Colorado Supreme Court will hear arguments next Tuesday in a case where a divorced couple disagrees on what should happen to the embryos they had created and frozen years earlier. Numerous such cases have been settled across different states, with no consistent ruling. The central issue in this case weighs one person’s constitutional right to procreate against another person’s right not to. The case could move on to the U.S. Supreme Court, where a ruling would apply nationwide. (Washington Post)

• This year’s flu season is shaping up as a memorably bad one; influenza researchers are now warning that it could be one of the worst in history. The primary reason is a rapid spike in infections caused by the virus known as H3N2, which many scientists describe as the most troublesome in the viral family. H3N2 is known for its ability to mutate rapidly — one of its adaptions makes it unusually difficult to study and predict. Equally daunting, it has proved difficult to design strong protection against this strain; A meta-analysis looking at vaccine effectiveness studies from 2004 to 2015 suggests the current vaccine is, at best, 33 percent effective against H3N2. (STAT)

• Astronomers report that the Milky Way’s central hub, fondly known as the bulge, is a “dynamic environment of variously aged stars zipping around at different speeds, like travelers bustling about a busy airport.” The finding — based on a nine-year analysis of Hubble Space Telescope data — should deepen scientists’ understanding of the heart of our galaxy, long thought to be a kind of old-age home for stars formed shortly after the Big Bang. The researchers, led by William Clarkson of the University of Michigan, Dearborn, studied the chemical composition of about 10,000 Sun-like stars in the bulge and concluded that many were rich in heavy elements — indicating they were much newer (and faster-moving) than stars richer in hydrogen and helium. (NASA)

• A new study in the journal Current Biology reports that the proportion of male-to-female green sea turtles is dramatically dropping due to rising ocean temperatures. The sex of a green sea turtle is determined by subtle temperature shifts in the environment; females hatch over what is known as the “pivot temperature,” 29.3 degrees Celsius, males hatch below the pivot. Scientists studying green sea turtles’ around their primary nesting grounds at Raine Island, off the eastern coast of Australia, have discovered that 99 percent of young sea turtles are now female. Sea turtles return to the same breeding grounds as their birth home to mate, so researchers fear that the population around the northern Great Barrier Reef will be negatively impacted over time. (Washington Post)

• With medical marijuana now legal in 29 states and some therapeutic use of cannabis compounds allowed in 17 others, scientists are spotting opportunities for an expansive new area on which to focus their careers. The plant’s precise health benefits (and hazards) remain poorly understood — in part because conducting research has long been stymied by marijuana’s illegal status. Today, given a lack standardization and compositional understanding of commercially-sold medical marijuana, some scientists are seeing both jobs and entrepreneurial opportunities — though the lingering stigma attached to the drug may still present some career downsides. (Science)

• And finally: One thing most people who have tried smoking a cigarette have in common: they’ve gone on to become regular smokers, at least for a temporary period of time. An analysis of global survey data indicates that an estimated 68.9 percent of individuals smoked daily after trying a cigarette. “[This shows] prevention, providing [fewer] opportunities or reasons for young people to try a cigarette, is a good idea,” said Peter Hajek, co-author of the research, which was published in November in the journal Nicotine and Tobacco Research. While smoking prevalence has decreased, the number of smokers worldwide stands at close to one billion, with numbers expected to rise with global population. (The Guardian)