A paper that appeared in Scientific Reports by Evans et al. (1)asked whether changes in the genotypes of target mosquito populations would occur due to introgression of released transgenic mosquito genomes. The paper in fact describes the introgression of released mosquito strain genome into wild populations of Aedes aegypti after releases of the OX513A strain developed by Oxitec and the paper has generated a lot of controversy. Is this a surprising finding or an entirely predictable outcome? Is it cause for alarm?
Mark Benedict's blog
Teams testing mosquitoes that are being considered for field release, their advisors, policy makers and donors often talk about ‘large cage trials’, but how large must a cage be for mosquito trials to qualify for that title? Is the proper metric its volume or stimulation of behavioral characteristics for a cage that provides the data we need? Perhaps the real value of large cage testing is neither of these but its independence.
It is often asserted that there are two malaria vector interventions in widespread use: long-lasting insecticide treated bednets (LLIN) and indoor residual insecticide spraying (IRS). Are either of these vector interventions? I’ll argue that the answer is, “No!” What does this mean for the development of new methods?
It’s a useful reminder to consider what one must have for successful genetic control strains for mosquitoes. While the focus is often on effectors for specific population manipulations, there are other bits “under the hood” that, like an engine, can’t really be ignored. It’s easy to forget how necessary these are when concentrating on something novel. I’ll give you my bare-bones list of basic genetic control features that sooner or later, you simply must have.
There is too little appreciation in current vector-borne disease paradigms for the intervention characteristics that are appropriate for stop-gap emergencies vs. those that are vital for the end-game: elimination. Regardless of whether you think elimination of any vector-borne disease is possible, it will not be accomplished without this.
It is said that predictions are very difficult – especially when they concern the future. No doubt Scott O’neil and his Eliminate Dengue team never would have expected to be where they are now 10 years ago. In contrast, those who dreamt of releasing malaria-refractory transgenic mosquitoes two decades ago in the Tucson desert would have been surprised too.
Seldom does so much news appear so suddenly that it grabs me by the ears and says, “You MUST write a blog. Now!” Following are the highlights of recent publications that reflect the maturing potential for genetic control to affect malaria and dengue transmission. If you’re interested in a quick summary of recent news and views, here it is.
A friend and colleague asked me whether all the media excitement about transgenic mosquitoes represents real accomplishments that beat non-transgenic sterile insect technique (SIT). Good question. In the first of a two-part blog, I’ll tell you where I think things stand, first in SIT. In the second part, I’ll look at population replacement.
One thing that the poorest living in developing countries recognize is real hazard. What does this mean for those planning to implement genetic control programs?
I blogged recently that getting the facts out about genetic engineering of mosquitoes would not be enough to persuade those who are hard anti-GM activists that they can be safely developed. I also argued that becoming an activist allowed one to abandon the bothersome constraints of truth. AAAS appears to agree with me, but have they made the right call?