What’s sex got to do with it? Malaria might be eradicated

prototype-mosquitos-modifiedA milestone was achieved in exciting research from Imperial College London which could eliminate malaria within decades. Researchers have applied new CRISPR-cas9 genetic techniques to alter mosquitoes’ sexual development.

While currently there is no vaccine for the disease that affects 216 million people worldwide, biotechnologists have perfected a man-made genetic technology which manipulates DNA in a technique referred to as “gene drive”.

The process spreads copies of a gene that stops female mosquitos from biting and laying eggs, so that after 7 to 11 generations there is a complete loss of normal females having any offspring. A report in Nature describes how mosquito populations in controlled cages were eradicated after a few genetically modified insects were introduced to the colonies.

Lead researcher, Andrea Crisanti explained that although the female mosquitoes became infertile, the male populations spread the deadly gene to a dwindling progeny. “It could be almost five years before the gene-drive mosquitoes are tested in the wild…but it’s promising”.

To eradicate malaria, Zika and other mosquito borne viruses, though, requires mankind to eradicate mosquitoes from the planet—a bold and potentially irreversible step. Though the gene drive technology seems to have been proven effective in controlled cage studies, what are the broader ethical implications for deliberately expanding the list of extinct species to kill off mosquitoes? International health improvement imperative? Back yard nuisance abatement? Dangerous step over a biotechnology precipice?

For those worried about the “butterfly effect” of killing ALL the mosquitoes in the world, Professor Scott Ritchie at James Cook University has built a better mozzie trap for the back garden that uses water and nets instead of a killer gene drive.

Read more: Nature / Technology Review / NY Times / NPR (1) / NPR (2)

Image: Kyrou et all / CC-BY 4.0

This story is taken from the 28 September 2018 edition of The Warren Centre’s Prototype newsletter. Sign up for the Prototype here.