New genetic front in war against malaria

They are as old as the dinosaurs and kill nearly 250,000 people a month. The war against malaria is now proceeding on many fronts, from preventative measures to the introduction of more effective drugs.

Now, a group of scientists, including one from the University of California, Riverside, has discovered a long-hypothesized male determining gene in the mosquito species that carries malaria, laying the groundwork for the development of strategies that could help control the disease.

In many species, including mosquitoes, Y chromosomes control essential male functions, including sex determination and fertility. However, knowledge of Y chromosome genetic sequences is limited to a few organisms.

The discovery of the putative male-determining gene, which was outlined in a paper, provides researchers with a long-awaited foundation for studying male mosquito biology.

This is significant because male mosquitoes offer the potential to develop novel vector control strategies to combat diseases, such as malaria and the zika and dengue viruses, because males do not feed on blood or transmit diseases.

The researchers used multiple genome sequencing techniques, including single-molecule sequencing and Illumina-based sex-specific transcriptional profiling, as well as whole-genome sequencing, to identify an extensive dataset of Y chromosome sequences and explore their organization and evolution in Anopheles gambiae complex, a group of at least seven morphologically indistinguishable species of mosquitoes in the genus Anopheles which contain some of the most important vectors of human malaria.

They found only one gene, known as YG2, which is exclusive to the Y chromosome across the species complex, and thus is a possible male-determining gene.

The study is published online in the journal Proceedings of the National Academies of Sciences.