title: Aberrant Time to Most Recent Common Ancestor as a Signature of Natural Selection.
abstract: Natural selection inference methods often target one mode of selection of a particular age and strength. However, detecting multiple modes simultaneously, or with atypical representations, would be advantageous for understanding a population's evolutionary history. We have developed an anomaly detection algorithm using distributions of pairwise time to most recent common ancestor (TMRCA) to simultaneously detect multiple modes of natural selection in whole-genome sequences. As natural selection distorts local genealogies in distinct ways, the method uses pairwise TMRCA distributions, which approximate genealogies at a nonrecombining locus, to detect distortions without targeting a specific mode of selection. We evaluate the performance of our method, TSel, for both positive and balancing selection over different time-scales and selection strengths and compare TSel's performance with that of other methods. We then apply TSel to the Complete Genomics diversity panel, a set of human whole-genome sequences, and recover loci previously inferred to be under positive or balancing selection.
authors.affiliation: Department of Biological Statistics and Computational Biology, Cornell University hsh37@cornell.edu.
authors.forename: Haley
authors.initials: H
authors.lastname: Hunter-Zinck
authors.affiliation: Department of Molecular Biology and Genetics, Cornell University.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Clark
mesh_terms: D000465:Algorithms; D003710:Demography; D056426:Genetic Loci; D023281:Genomics; D006801:Humans; D010802:Phylogeny; D011156:Population Density; D012641:Selection, Genetic; D013997:Time Factors
keywords: anomaly detection; natural selection; time to most recent common ancestor