A team of researchers has found a gene on the Y chromosome of mosquitoes that is lethal to any females that inherit it. The team’s findings may help scientists develop better methods of mosquito control. The details are in a paper that was just published in the journal eLife.
The mosquito species Anopheles stephensi are the primary vectors of malaria and transmit the parasite when they bite humans. Male mosquitoes don’t bite and so don’t transmit any pathogens. Female mosquitoes, on the other hand, require the energy from blood in order to lay eggs. Past pest control techniques have often focused on changing sex ratios to favor males.
Researchers from Virginia Tech found a gene called Guy1 on the Y chromosome of A.stephensi mosquitoes. Y chromosome genes tend to be poorly studied; their small size and repeat-rich regions make it difficult to use traditional methods of genetic analysis. The newly discovered gene codes for GUY1, a small protein of only 56 amino acids in length. The protein is involved in embryonic development but the team found that it was lethal to any females that inherited two copies of the gene. This wouldn’t happen naturally but the researchers were able to see the effect by adding a copy to a non-sex chromosome. Males were unaffected by having two copies. The team found that males with Guy1 were actually more reproductively successful than males without the gene.
The team hopes to use their findings to develop new methods of controlling the spread of malaria by eliminating female A.stephensi mosquitoes. Guy1 is only passed down to half the female offspring, making it possible for 50% of females to survive. The research team believes they can get around this problem by using gene editing techniques.
Malaria is a dangerous disease and a leading cause of death in many parts of the world. The best way to control the disease is to eradicate the vectors, female mosquitoes. The discovery of the Guy1 gene may help researchers develop efficient forms of pest control.
Frank Criscione et al. GUY1 confers complete female lethality and is a strong candidate for a male-determining factor in. eLife (2016).