Chau bites? They discover the gene that helps mosquitoes detect human sweat

Female mosquitoes bite us because they need nutrients from our blood (and those from vertebrates) to lay their eggs. How do they detect us? What attracts them is the carbon dioxide we breathe as well as the lactic acid from our sweat. Until here, history known. However, a group of scientists from the Tropical Genetics Laboratory in Miami (USA) went a step further.

Based on this prior knowledge, they wanted to determine what was activated to attract mosquitoes. It's like that that they found that the protagonist in the smell of these insects is a gene that detects lactic acid. This is the IR8a gene that turns them into bloodhounds.

To confirm their hypothesis, the researchers took the species Aedes aegypti – Transmitter, among other things, dengue fever and yellow fever – and eliminates the gene mentioned with the help of the CRISPR-Cas9 genetic editing technique. Then they mixed them with common mosquitoes and, thanks to one of the experts who gave their arm to science, they were able to confirm that only the insects carrying the gene attacked his arm, while the others completely ignored his presence (at least during the first four minutes of exposure).

"When the IR8a gene is eliminated in the laboratory, the insect loses its ability to react to volatile acids and with that, about 50% of their attention by humans, "explained Matthew DeGennaro, lead author of the article published in the scientific journal, to foreign media. Current biology.

What is this discovery for? Found genetic material that helps them identify humans, specialists would be able to improve the production of repellents and traps, to hide this particular smell and thus confuse mosquitoes. "The smells that mask the IR8a pathway could improve the effectiveness of current repellents, so we would help prevent people from being the main prey of these insects," concluded DeGennaro.