Of late there have been a number of breakthroughs in combating mosquito-borne diseases. The latest is the sequencing of the Aedes aegypti mosquito’s genome by an international team of researchers. This is a shot in the arm for the fight against yellow fever and dengue that takes a toll of thousands of lives each year in the developing world. Like the Anopheles gambiae, its infamous cousin that carries malaria, the Aedes mosquito transmits viruses as it feeds on human blood. But the resemblance ends there. For the researchers who unscrambled the Aedes genome found it to be five times larger than that of Anopheles. And unlike Anopheles’, the Aedes genome is top-heavy with ‘junk DNA’, whose function is unclear.
Genomes are the biological instruction manuals for how an organism forms and how its cells function. Now that scientists have decoded the Aedes genome, it may not be long before they figure out suitable drugs and vaccines to stop it from offering piggyback rides to viruses that cause yellow fever and dengue fever. Or create genetically modified (GM) versions of this mosquito that are unable to transmit the viruses. Researchers from the Johns Hopkins University recently did this by producing the Anopheles’ GM avatar, altering the insects to make a protein that blocked the malaria parasite from invading the mosquito after its blood meal. Another strategy would be to compare human genes with those of disease-causing microbes to find key biological pathways that exist in the parasite but not in people and develop drugs accordingly.
Having said that, the developed countries — where such cutting edge research is carried out — must show the political will to translate this hi-tech genome research into low-tech control strategies for the developing countries. Only then will we be able to eradicate these diseases from the world altogether.