"DNA sequences of complete genomes provide us with a direct record of evolution", says Peer Bork, Associate Coordinator for Structural and Computational Biology at EMBL, whose group carried out the project. "For a long time the overwhelming amount of data (the human genome alone contains enough information to fill 200 telephone books) has made it very difficult to pinpoint the information needed for a high-resolution map of evolution. But our study shows how this challenge can be tackled by combining different computational methods in an automated process."
Bork's lab specialises in the computational analysis of genomes, and recently they applied this expertise to the tree of life. Since all organisms descend from the same ancestor, they share some common genes. Francesca Ciccarelli and Tobias Doerks of Bork's group managed to identify 31 genes with clear relatives in 191 organisms, ranging from bacteria to humans, to reconstruct their relationships.
"Even using such genes, you might get the wrong answer," says Ciccarelli. "Organisms inherit most genes from their parents, but over the course of evolution, a few have been obtained when organisms swapped genes with their neighbours in a process called horizontal gene transfer (HGT). Obvio
Contact: Anna-Lynn Wegener
European Molecular Biology Laboratory