New York, January 25: Genetic molecules in dengue-causing mosquitoes may hold the key to halting the spread of the deadly fever, and other such diseases, an Indian-origin researcher has found. The study may lead to future breakthroughs in combating destructive tropical diseases like dengue fever, Zika virus and yellow fever. The researchers focused their efforts on a single species of mosquito, Aedes aegypti, a key player in the spread of such diseases in animals and humans around the world.

"Given the widespread global distribution of the Aedesaegypti mosquito, we estimate over 40 percent of the world's population is at risk from dengue," said Susanta K Behura, an assistant research professor at the University of Missouri in the US.

"The research could be used to precisely modify the genetic material of mosquitoes, preventing them from spreading a disease to humans," said Behura.

Recent research has shown that fragments of transfer RNA(tRFs), small sections of RNA that can regulate gene expression, play a role in the development of a disease. This prompted Behura and his colleagues to collect samples from mosquitoes around the world, which then underwent molecular analysis.

In analysing TRF response to a variety of conditions and stimuli - including sex, developmental stage and exposure to the dengue virus - the team found that a specific TRF was expressed differently when exposed to each of these conditions. In particular, the sex-biased expression was important, as only female mosquitoes feed on blood and spread diseases to humans, researchers said.

They said that this particular TRF is a promising candidate for further study, raising the possibility of a targeted approach to halting the spread of dengue fever. "We do not have vaccines for all the different viral diseases caused by this mosquito," Behura said. "Currently, the best way to fight these mosquitoes is to control them, and the rational way to control human infections is to make them incapable of spreading the disease," he said.