This work mitigates a big issue with the first gene drive systems, which is the accumulation of drive-resistant mosquitoes that could still transmit malaria parasites,” said UCI vector biologist Anthony James. Steve Zylius / UCI
New CRISPR-based gene drive approach successfully overcomes issue of resistance in females
Employing a strategy known as “population modification,” which involves using a CRISPR-Cas9 gene drive system to introduce genes preventing parasite transmission into mosquito chromosomes, University of California researchers have made a major advance in the use of genetic technologies to control the transmission of malaria parasites.
University of California, Irvine postdoctoral researcher Adriana Adolfi, in collaboration with colleagues at UCI, UC Berkeley and UC San Diego, followed up on the group’s pioneering effort to develop CRISPR-based gene drive systems for making mosquito vectors resistant to transmitting malaria parasites by increasing gene drive effectiveness in female mosquito progeny.
“This work mitigates a big issue with the first gene drive systems, which is the accumulation of drive-resistant mosquitoes that could still transmit malaria parasites,” said UCI vector biologist Anthony James, the Donald Bren Professor of Microbiology & Molecular Genetics and Molecular Biology & Biochemistry, who was a co-primary investigator on the study.
“The second-generation gene drive system described in this paper can be applied to any of the several thousand genes that are essential for insects to survive or reproduce,” said UC San Diego Distinguished Professor Ethan Bier, a co-author of the study and science director at the Tata Institute for Genetics and Society. “While it was developed in fruit flies, this system is readily transportable to a broad selection of insect species that serve as vectors for devastating disorders such as Chagas disease, sleeping disease, leishmaniasis and arboviral diseases.”
Study results appear in Nature Communications. Link to study: https://www.nature.com/articles/s41467-020-19426-0
They describe a highly efficient second-generation version of the team’s original gene drive, developed for the Indo-Pakistani malaria vector mosquito Anopheles stephensi. The 2015 work, published in Proceedings of the National Academy of Sciences, was the first demonstration of a CRISPR-based gene drive in mosquitoes.
In that first study, the gene drive was transmitted to about 99 percent of progeny when the parent in which the gene drive was inserted was a male but only 60 to 70 percent of offspring when the parent in which the gene drive was inserted was a female. A significant number of drive-resistant chromosomes are generated in females; this, in principle, could allow those females to continue to transmit parasites.
Adolfi, lead author of the new study, and collaborators solved the failure to drive efficiently through females by equipping the gene drive with a functional copy of the target gene into which the drive is inserted. Normal function of this target gene is required in this mosquito species for female survival and fertility after she feeds on blood, and its functionality is usually disrupted when the drive system is inserted into the gene.
The resulting female mosquitoes showed strong and consistent drive in a population cage study and negligible production of drive-resistant chromosomes. This strategy of inserting a gene drive into a gene essential for viability or fertility and at the same time including a functional gene that rescues the loss of viability or fertility provides a general solution to drive resistance through females. Also, as with a catalytic converter removing combustion pollution from automobiles, the new system efficiently eliminates genetic errors made in the drive process.
This gene drive system – in combination with genes for blocking parasite transmission – can now be used to design field-ready strains of mosquitoes. Thorough testing is required to demonstrate safety and efficacy before advancing to field testing.
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
Blocking malaria transmission
- Bill Gates predicted a pandemic in 2018. Now that COVID-19's arrived, here's how he wants to control it.on November 10, 2020 at 6:11 pm
Philanthropist Bill Gates implicated a lack of leadership in the U.S. response to COVID-19 during an event with Stanford Medicine.
- Study opens a new avenue for prophylactic anti-malarial strategieson November 6, 2020 at 6:56 am
If we are able to block parasite proteins or the repair process, we are able to prevent infection of the liver by Plasmodium parasites, preventing malaria before the parasite can cause any harm.
- UC researchers pioneer more effective method of blocking malaria transmission in mosquitoeson November 5, 2020 at 4:15 am
This gene drive system — in combination with genes for blocking parasite transmission — can now be used to design ... which resulted from collaborations between the UC Irvine Malaria Initiative and ...
- Using Infections to Fight Infectionson November 3, 2020 at 4:00 pm
This work was supported by funds from the Johns Hopkins Malaria Research Institute ... Evaluate these strains in their ability to block Plasmodium transmission by Anopheles mosquitoes.
- Researchers pioneer more effective way to block malaria transmission in mosquitoeson November 3, 2020 at 11:42 am
University of California - Irvine. (2020, November 3). Researchers pioneer more effective way to block malaria transmission in mosquitoes: New CRISPR-based gene drive approach successfully ...
Go deeper with Google Headlines on:
Blocking malaria transmission
Go deeper with Bing News on:
CRISPR-based gene drive
- Metagenomi closes USD 65 million Series A financing led by Leaps by Bayer and Humboldt Fundon November 12, 2020 at 4:17 am
Metagenomi, a next generation gene editing company launched by UC Berkeley scientists in 2018, successfully completed a USD 65 million Series A financing round and emerged from stealth mode today. The ...
- The ethical way to alter organismson November 9, 2020 at 2:06 am
One of the inventors of CRISPR-based gene drive has some advice to improve science, ethics, and the odds that these technologies will one day save millions of lives.
- Stanford develops CRISPR 'lab on a chip' for detecting COVID-19on November 6, 2020 at 8:20 am
Researchers at Stanford University have developed a CRISPR-based “lab on a chip” to detect COVID-19, and are working with automakers at Ford to develop their prototype into a market-ready product.
- A digital CRISPR-based method for quick detection and absolute quantification of SARS-CoV-2on November 4, 2020 at 4:00 pm
Likewise, CRISPR-based methods can also detect SARS-CoV-2 ... This research endeavor, led by Dr. Xiaolin Wu from the Singapore-MIT Alliance for Research and Technology, reveals an optimized ...
- Researchers pioneer more effective way to block malaria transmission in mosquitoeson November 3, 2020 at 12:36 pm
Employing a strategy known as 'population modification,' which involves using a CRISPR-Cas9 gene drive system to introduce genes preventing parasite transmission into mosquito chromosomes, researchers ...