New Perspectives on Gene Family Evolution: Losses in Reconciliation and a Link with Supertrees

Reconciliation between a set of gene trees and a species tree is the most commonly used approach to infer the duplication and loss events in the evolution of gene families, given a species tree. When a species tree is not known, a natural algorithmic problem is to infer a species tree such that the corresponding reconciliation minimizes the number of duplications and/or losses. In this paper, we clarify several theoretical questions and study various algorithmic issues related to these two problems. (1) For a given gene tree T and species tree S, we show that there is a single history explaining T and consistent with S that minimizes gene losses, and that this history also minimizes the number of duplications. We describe a simple linear-time and space algorithm to compute this parsimonious history, that is not based on the Lowest Common Ancestor (LCA) mapping approach; (2) We show that the problem of computing a species tree that minimizes the number of gene duplications, given a set ...

• Type: Conference
• Year: 2009
• Where: RECOMB
• Authors: Cedric Chauve, Nadia El-Mabrouk
• Keywords: Computational Biology, Gene Duplications, Gene Trees, RECOMB 2009, Species Tree