Luay Nakhleh
Computer Science and Biochemistry and Cell Biology at Rice UniversityAdjunct Assistant
Professor of Systems Biology at MD Anderson Cancer Center

For more information please contact Dr. David Bader

"Accurate Inference of Phylogenetic Relationships from Multi-locus Data"

Abstract:

Accurate inference of phylogenetic relationships of species, and understanding their relationships with gene trees are two central themes in molecular and evolutionary biology. Traditionally, a species tree is inferred by (1) sequencing a genomic region of interest from the group of species under study, (2) reconstructing its evolutionary history, and (3) declaring it to be the estimate of the species tree. However, recent analyses of increasingly available multi-locus data from various groups of organisms have demonstrated that different genomic regions may have evolutionary histories (called“gene trees”) that may disagree with each other, as well as with that of the species. This observation has called into question the suitability of the traditional approach to species tree inference. Further, when some, or all, of these disagreements are caused by reticulate evolutionary events, such as hybridization, then the phylogenetic relationship of the species is more appropriately modeled by a phylogenetic network than a tree. As a result, a new, post-genomic paradigm has emerged, in which multiple genomic regions are analyzed simultaneously, and their evolutionary histories are reconciled in order to infer the evolutionary history of the species, which may not necessarily be treelike.  In this talk, I will describe our recent work on developing mathematical criteria and algorithmic techniques for analyzing incongruence among gene trees, and inferring phylogenetic relationships among species despite such incongruence. This includes work on lineage sorting, reticulate evolution, as well as simultaneous treatment of both. If time permits, I will describe our recent work on population genomic analysis of bacterial data,and the implications on the evolutionary forces shaping the genomic diversity in these populations.

Bio:

Luay Nakhleh is an Assistant Professor of Computer Science and Biochemistry and Cell Biology at Rice University, and an adjunct Assistant Professor of Systems Biology at MD Anderson Cancer Center. He received the B.Sc. degree from the Technion, Israel Institute of Technology, in 1996, the Master’s degree from Texas A&M University in 1998, and the PhD degree from the University of Texas at Austin in 2004⎯all three degrees in Computer Science. His research interests fall into the general areas of computational biology and bioinformatics; in particular, he works on computational phylogenomics and population genomics, and their connections with other fields in biology. Luay has published over 50 manuscripts on his work, supervised the dissertations of two recent PhD graduates, and currently supervises the dissertations of 6 PhD students. Luay has received several awards, including the Texas Excellence Teaching Award from UT Austin in 2001, the Outstanding Dissertation Award from UT Austin in 2005, the Roy E. Campbell Faculty Development Award from Rice University in 2006, the DOE Early Career Award in 2006, the NSF CAREER Award in 2009, the Phi Beta Kappa Teaching Prize in 2009, and an Alfred P. Sloan Foundation Fellowship in 2010.