The ability to quickly alter the code of life has given us unprecedented power over the natural world. Should we use it?
Mosquitoes infect hundreds of thousands of people (and animals) each year. This article discusses how we can change their DNA - and whether we should. And ... all the other implications of doing so.
More often than not, it seems that when we mess with nature, we screw things up. With the diseases spread by mosquitoes, is it worth the risk? In Florida, due to the Zika virus, we're going to find out.
There are approximately 3,500 species of mosquito, but James pays attention to just a few, each of which ranks among the deadliest creatures on Earth. They include Anopheles gambiae, which transmits the malaria parasite that kills hundreds of thousands of people each year. For much of his career, however, James has focused on Aedes. Historians believe the mosquito arrived in the New World on slave ships from Africa in the 17th century, bringing with it yellow fever, which has killed millions of people. Today the mosquito also carries dengue fever, which infects as many as 400 million people a year, as well as such increasingly threatening pathogens as chikungunya, West Nile virus, and Zika.
It's not just about mosquitoes, though.
No scientific discovery of the past century holds more promise—or raises more troubling ethical questions. Most provocatively, if CRISPR were used to edit a human embryo’s germ line—cells that contain genetic material that can be inherited by the next generation—either to correct a genetic flaw or to enhance a desired trait, the change would then pass to that person’s children, and their children, in perpetuity. The full implications of changes that profound are difficult, if not impossible, to foresee.
There are ethical questions, as well as implications on other species.
Combating the Ae. aegypti mosquito, which carries so many different pathogens, would require a slightly different approach. “What you would need to do,” he told me, “is engineer a gene drive that makes the insects sterile. It doesn’t make sense to build a mosquito resistant to Zika if it could still transmit dengue and other diseases.”
To fight off dengue, James and his colleagues have designed CRISPR packages that could simply delete a natural gene from the wild parent and replace it with a version that would confer sterility in the offspring. If enough of those mosquitoes were released to mate, in a few generations (which typically last just two or three weeks each) entire species would carry the engineered version.
James is acutely aware that releasing a mutation designed to spread quickly through a wild population could have unanticipated consequences that might not be easy to reverse. “There are certainly risks associated with releasing insects that you have edited in a lab,” he said. “But I believe the dangers of not doing it are far greater.”
Please read the entire article (plus the embedded link, if you have time) and provide your thoughts.
Note: I have blockquoted everything posted from the National Geographic article, but some of it isn't showing up as such. I will keep trying to fix it.