Sequencers come together

An international collaboration of genome sequencing teams previously at odds over strategy puts aside its differences this week in Nature to publish the third complete mammalian genome sequence. The Rat Genome Sequencing Project Consortium combined whole genome shotgun (WGS) methodology with a clone-by-clone approach to produce a high-quality draft covering over 90% of the brown Norway rat (Rattus norvegicus) genome.

The team sequenced bacterial artificial chromosome (BAC) clones to produce a 1x-coverage of the rat genome and used data from each BAC to identify the matching sequences from the WGS data using its own purpose-built software. “It was a real combined strategy, bringing the two things together in real time,” said Richard A. Gibbs, director of Baylor College of Medicine Human Genome Sequencing Center and principal author of the paper.

Sequencing teams have been engaged in a robust debate over the merits of WGS. Despite the success of the rat ...