Two papers and a news item not to be missed. The first one is “Genome-edited powdery mildew resistance in wheat without growth penalties” published in Nature by a Chinese team led by Caixia Gao.
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Anti-CRISPR proteins are the rock needed to stop CRISPR-based mosquito-eradicating gene drives, if necessary, and make them safer. In a news feature published last year in Nature, the molecular parasitologist Andrea Crisanti disclosed unpublished data about halting an anti-malaria gene-drive system by adding anti-drive mosquitoes to the mix. “They can completely, 100% block the drive. We can stop the [Anopheles gambiae] population from crashing,” he said. According to the scientist from the Imperial College London, it’s kind of like buying an insurance. Looking ahead to field-testing his sterilization strategy, Crisanti imagined having cages of anti-drive mosquitoes at the ready, just in case things go awry. Well, that work is now published, and anti-drive mosquitoes are a reality. To learn more, see the paper published on June 25 in Nature Communications by Chrysanthi Taxiarchi et al.
This is an issue for all tastes and interests. Don’t miss (Broken) Promises of Sustainable Food and Agriculture through New Biotechnologies by Todd Kuiken, Rodolphe Barrangou and Khara Grieger; A Code of Ethics for Gene Drive Research by George Annas and other members of the Controlling and Countering Gene Editing in Mosquitoes research project funded by the DARPA Safe Genes program; The Cas9 Hammer and the Sickle by Fyodor Urnov.
I binge-watched Unnatural Selection, as many CRISPR enthusiasts have done. My review in a few words: the Netflix miniseries is a patchwork of bad and good. On the minus side, too many biohackers and too little real science. On the plus side, some interesting reporting on social issues, such as public engagement of local communities and the challenge of patient access to novel therapies. To sum up: episode 1 on biohacking is the worst, episode 3 on gene drives is the best. So my advice is: don’t give up at the first disappointing scenes. You might want to, but do not stop.
The trolley problem is a classic philosophical dilemma, and its variants have been used extensively to test moral intuitions. Scanning the brain of human subjects with functional MRI during task performance has proven useful to understand how emotion and reason interact when we ponder bioethical issues. It would be interesting to adopt those approaches to study the psychological barriers towards controversial innovations such as gene drives. Just imagine you alone are responsible for pressing a button and switching on gene drives in malaria-spreading mosquitoes. Someone is going to die, and you must decide whom to save. Continue reading
Choose a word to fill the gap in the sentence. “Gene drives are an ambitious experiment in …”. Genetics? Ecology? Evolution? Obviously, gene drives are all this and more. They may also represent a significant social experiment in risk communication, public engagement, participatory processes. Potential applications of this technology include controlling the transmission of vector-borne diseases and eliminating invasive species from sensitive ecosystems. We do not yet know if these genetic elements, designed to foster the preferential inheritance of a gene of interest with CRISPR’s help, will work in field trials as hoped. To find out, a green light to test this technology out of the labs will have to be negotiated with the public, stakeholders, regulators, and governments of affected countries. A first step in this direction was taken last week with the commitment to respect shared guiding principles in gene drive research and communication published in Science by the technology main sponsors and supporters. Signatory organizations are scattered around the world, from the US to India, with the Bill & Melinda Gates Foundation at the forefront with its Target Malaria project. Continue reading
“Safe genes” is what it’s called, and it’s a program for the responsible development of gene editing technologies funded with $65 million by the US Defense Advanced Research Projects Agency (Darpa). The grant will go to seven teams including top scientists such as CRISPR co-inventor Jennifer Doudna and synthetic biologist George Church. Finding reversible ways to control gene editing is a national security issue, in the event CRISPR falls into the wrong hands. But Darpa intends also to foster peaceful applications, by encouraging innovation and mitigating risks which might accidentally arise in civilian labs. Think of new CRISPR variants that can distinguish between highly similar genetic sequences, or molecular mechanisms to finely modulate the technology of gene drives, which is experimented to propagate modifications through entire populations. Continue reading
Mosquito nets are not enough, vaccines are late to come, land reclamation in Africa is a challenge. But there is a new hope for defeating malaria, coming directly from the most advanced CRISPR frontier. The trick is a kind of genetic chain reaction fuelled by genetic elements called “gene drives”. Researchers are experimenting their power with the aim of crashing the number of mosquitoes responsible for Plasmodium transmission, by spreading genes that are bad for Anopheles gambiae. A gene behaving in Mendelian way has a 50% chance of being passed on from parent to offspring, but it can virtually reach 100% with a little help from a drive. Thus a gene designed to damage a harmful species can propagate within a few generations with a domino effect, until the population collapses. One of the founders of this futuristic strategy is an Italian molecular parasitologist: Andrea Crisanti, of the London Imperial College. We asked him to explain times and ways, strengths and risks of this approach. Continue reading
CRISPeR FRENZY 