SPL

Get it while it's hot: the blood-sucking malaria mosquito comes under genome scrutiny.

The next creatures to have their genomes sequenced will be the laboratory rat and the mosquito chiefly responsible for spreading malaria in sub-Saharan Africa.

The plan to sequence the 260 million base pairs of the mosquito Anopheles gambiae was announced this week by a consortium of researchers and sequencing centres.

US company Celera Genomics and Genoscope, the French national sequencing centre, will carry out the initial sequencing using the whole-shotgun technique. They will break the genome into fragments and sequence the DNA of each piece; Celera will reassemble these into a full sequence. Other centres will help to finish and annotate it.

The team expects the project to cost less than $10 million and be ready, as a rough draft, by the end of the year. The French government will part-fund the effort, and the consortium hopes that US agencies and the European Union will provide the rest.

Malaria infects three million people and kills one and a half million each year.

"The sequence will be enormously valuable," says Steven Sinkins, who studies mosquito genetics at the Liverpool School of Tropical Medicine. "It will transform what we can do on a molecular genetics level."

It will help researchers find genes that let mosquitoes carry and transmit the malaria parasite, he predicts, as well as shedding light on insecticide-resistance. Many traits have been loosely traced to genome regions, but Sinkins says the new work should let researchers focus on individual genes or particular metabolic pathways.

The rat genome — containing an estimated three billion base pairs, similar to the human genome — will be sequenced by Celera Genomics and the Baylor College of Medicine, Houston, sharing a $58 million grant from the US National Institutes of Health. They aim to finish in two years.