Could we make all mosquitoes one sex?
Lorne Henry says, “I heard a talk by someone who is specialising in trying to rid the world of the malaria mosquito or of the disease and I had an idea about it: if those mosquitoes could be made all one sex - bingo!” So, could skewing the sex ratio get rid of mozzies?
This is a great idea, and exactly what Dr Nikolai Windbichler and his team at Imperial College, London, are trying to do. Kat Arney asked him how... Nikolai:: Well, the idea is if you progressively shift the sex ratio of a population towards males and there are fewer and fewer females in the population then the overall size of the population will decrease up to a point where the population cannot sustain itself any more and will actually crash.
Kat:: What did you do to try and skew this sex ratio?
Nikolai:: So, we introduced into the mosquito a gene which essentially destroys the X chromosome. As you know, as in humans, also in mosquitoes, there are two types of sperm produced by males: sperm that carry the Y chromosome and sperm that X chromosome. The sperm that carry a Y chromosome produce sons. The sperm that carry X chromosome produce daughters. So, we found a way to specifically eliminate the sperm that carried the X chromosome so that only the sperm that carried a Y chromosome would be functional and would make these males produce only sons. This is a very promising technology but we're still many steps away to rolling this out. We have both technical hurdles to overcome still, but also have to make sure that all aspects of biosafety, safety, ethical concerns and regulatory concerns would be addressed before we go any further with this. The next step is to take these mosquitoes and test them at a larger scale. We have tested the technology in small population cages, but we have a facility in Italy where we have larger cages that are a more field-like control environment. And there, we want to test the technology to see how it performs.
Kat:: Thanks to listener Lorne Henry and Dr Nikolai Windbichler - and there's a longer version of that interview on the Naked Scientists website. If you've got any questions about genes, DNA and genetics, just email them to me at firstname.lastname@example.org.