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Photo by James Gathany/CDC
Scientists say they have created mosquitoes that can introduce malaria-blocking genes into a mosquito population through their progeny and, ideally, eliminate the insects’ ability to transmit malaria to humans.
The researchers used the CRISPR gene-editing technique to insert a DNA element into the germ line of Anopheles stephensi mosquitoes.
These mosquitoes then passed on genes that may prevent malaria transmission to 99.5% of their offspring.
The scientists said further testing is needed to confirm the efficacy of this approach in preventing malaria transmission, but this is an important first step toward that goal.
“This opens up the real promise that this technique can be adapted for eliminating malaria,” said Anthony James, PhD, of the University of California, Irvine.
Dr James and his colleagues described the technique in PNAS.
In 2012, Dr James and his colleagues showed that antibodies that impair Plasmodium falciparum’s biology could be adapted from the immune systems of mice and introduced into mosquitoes. However, this trait could only be inherited by about half of the progeny.
Earlier this year, Ethan Bier, PhD, and Valentino Gantz, both of the University of California, San Diego, reported a new method for generating mutations in both copies of a gene in fruit flies. This mutagenic chain reaction involved using the CRISPR-associated protein 9 (Cas9) nuclease enzyme and allowed for transmission of mutations through the germ line with an inheritance rate of 95%.
The groups collaborated to fuse Dr Bier and Gantz’s method with Dr James’s mosquitoes. Gantz packaged antimalaria genes with a Cas9 enzyme and a guide RNA to create a genetic “cassette” that, when injected into a mosquito embryo, targeted a highly specific spot on the germ line DNA to insert the antimalaria antibody genes.
To ensure the element carrying the malaria-blocking antibodies had reached the desired DNA site, the researchers included in the cassette a protein that gave the progeny red fluorescence in the eyes. Nearly all offspring—99.5%—exhibited this trait.
Dr James said further testing will be needed to confirm the efficacy of the antibodies, and this could eventually lead to field studies.
“[The current study] is a significant first step,” he said. “We know the gene works. The mosquitoes we created are not the final brand, but we know this technology allows us to efficiently create large populations.” 
Photo by James Gathany/CDC
Scientists say they have created mosquitoes that can introduce malaria-blocking genes into a mosquito population through their progeny and, ideally, eliminate the insects’ ability to transmit malaria to humans.
The researchers used the CRISPR gene-editing technique to insert a DNA element into the germ line of Anopheles stephensi mosquitoes.
These mosquitoes then passed on genes that may prevent malaria transmission to 99.5% of their offspring.
The scientists said further testing is needed to confirm the efficacy of this approach in preventing malaria transmission, but this is an important first step toward that goal.
“This opens up the real promise that this technique can be adapted for eliminating malaria,” said Anthony James, PhD, of the University of California, Irvine.
Dr James and his colleagues described the technique in PNAS.
In 2012, Dr James and his colleagues showed that antibodies that impair Plasmodium falciparum’s biology could be adapted from the immune systems of mice and introduced into mosquitoes. However, this trait could only be inherited by about half of the progeny.
Earlier this year, Ethan Bier, PhD, and Valentino Gantz, both of the University of California, San Diego, reported a new method for generating mutations in both copies of a gene in fruit flies. This mutagenic chain reaction involved using the CRISPR-associated protein 9 (Cas9) nuclease enzyme and allowed for transmission of mutations through the germ line with an inheritance rate of 95%.
The groups collaborated to fuse Dr Bier and Gantz’s method with Dr James’s mosquitoes. Gantz packaged antimalaria genes with a Cas9 enzyme and a guide RNA to create a genetic “cassette” that, when injected into a mosquito embryo, targeted a highly specific spot on the germ line DNA to insert the antimalaria antibody genes.
To ensure the element carrying the malaria-blocking antibodies had reached the desired DNA site, the researchers included in the cassette a protein that gave the progeny red fluorescence in the eyes. Nearly all offspring—99.5%—exhibited this trait.
Dr James said further testing will be needed to confirm the efficacy of the antibodies, and this could eventually lead to field studies.
“[The current study] is a significant first step,” he said. “We know the gene works. The mosquitoes we created are not the final brand, but we know this technology allows us to efficiently create large populations.”
Photo by James Gathany/CDC
Scientists say they have created mosquitoes that can introduce malaria-blocking genes into a mosquito population through their progeny and, ideally, eliminate the insects’ ability to transmit malaria to humans.
The researchers used the CRISPR gene-editing technique to insert a DNA element into the germ line of Anopheles stephensi mosquitoes.
These mosquitoes then passed on genes that may prevent malaria transmission to 99.5% of their offspring.
The scientists said further testing is needed to confirm the efficacy of this approach in preventing malaria transmission, but this is an important first step toward that goal.
“This opens up the real promise that this technique can be adapted for eliminating malaria,” said Anthony James, PhD, of the University of California, Irvine.
Dr James and his colleagues described the technique in PNAS.
In 2012, Dr James and his colleagues showed that antibodies that impair Plasmodium falciparum’s biology could be adapted from the immune systems of mice and introduced into mosquitoes. However, this trait could only be inherited by about half of the progeny.
Earlier this year, Ethan Bier, PhD, and Valentino Gantz, both of the University of California, San Diego, reported a new method for generating mutations in both copies of a gene in fruit flies. This mutagenic chain reaction involved using the CRISPR-associated protein 9 (Cas9) nuclease enzyme and allowed for transmission of mutations through the germ line with an inheritance rate of 95%.
The groups collaborated to fuse Dr Bier and Gantz’s method with Dr James’s mosquitoes. Gantz packaged antimalaria genes with a Cas9 enzyme and a guide RNA to create a genetic “cassette” that, when injected into a mosquito embryo, targeted a highly specific spot on the germ line DNA to insert the antimalaria antibody genes.
To ensure the element carrying the malaria-blocking antibodies had reached the desired DNA site, the researchers included in the cassette a protein that gave the progeny red fluorescence in the eyes. Nearly all offspring—99.5%—exhibited this trait.
Dr James said further testing will be needed to confirm the efficacy of the antibodies, and this could eventually lead to field studies.
“[The current study] is a significant first step,” he said. “We know the gene works. The mosquitoes we created are not the final brand, but we know this technology allows us to efficiently create large populations.”