Reconstructing large regions of an ancestral mammalian genome in silico

Mathieu Blanchette

Center for Bioinformatics
McGill University

Date: Monday February 6, 2006
Time
: 12:20 p.m. - 1:20 p.m.
Location
: 367 Votey

Abstract

It is believed that most modern mammalian lineages arose from a series of rapid speciation events near the Cretaceous-Tertiary boundary. We show that such a phylogeny makes the common ancestral genome sequence an ideal target for reconstruction. Ancestral genome reconstruction raises a number of novel algorithmic questions, some which have very elegant solutions. Simulations suggest that with methods currently available, we can expect to get 98% of the bases correct in reconstructing megabase-scale euchromatic regions of an eutherian ancestral genome from the genomes of 20 optimally chosen modern mammals. Using actual genomic sequences from 19 extant mammals, we reconstruct 1.1 Mb of ancient genome sequence around the CFTR locus. Detailed examination suggests the reconstruction is accurate and that it allows us to identify features in modern species, such as remnants of ancient transposon insertions, that were not identified by direct analysis. In coming years, such reconstructions may help in identifying and understanding the genetic features common to eutherian mammals and may shed light on the evolution of human or primate-specific traits.

sponsored by CSSA

Computer Science Seminar