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 In a news feature published last year in Nature, the molecular parasitologist Andrea Crisanti disclosed unpublished data about halting an anti-malaria gene-drive system by adding anti-drive mosquitoes to the mix.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.
The idea is bold and seems to have worked fine. By using a DNA cutting enzyme to disrupt the X chromosome, researchers succeeded in distorting the sex ratio of offsprings, eventually leading to the all-male populations collapse. Andrea’s Crisanti and colleagues at the Imperial College London did it to caged Anopheles gambiae mosquitoes in their quest for a genetic strategy to beat malaria. Please see their paper in Nature Biotechnology and the Imperial College press release.Continue reading
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
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
The Italian city of Terni is now a spot on the map of cutting-edge research due to its new genetic-ecology lab, which is getting involved in the Target Malaria project funded by the Bill & Melinda Gates Foundation. For a couple of days, citizens are allowed to visit the facility which is part of the Genomics, Genetics and Biology Innovation Pole. That’s an example of real public engagement: everybody can talk to researchers and watch videos, but also enter the climatic rooms simulating tropical conditions and see the cages for the insects which are the tiny heroes and the target of a daring scientific challenge. The mission here in Terni indeed is to investigate if the idea of controlling genetically malaria, by introducing self-destroying Anopheles gambiae into wild mosquitoes populations, is set to work in real world situations. Continue reading