title: Mutation Is a Sufficient and Robust Predictor of Genetic Variation for Mitotic Spindle Traits in Caenorhabditis elegans.
abstract: Different types of phenotypic traits consistently exhibit different levels of genetic variation in natural populations. There are two potential explanations: Either mutation produces genetic variation at different rates or natural selection removes or promotes genetic variation at different rates. Whether mutation or selection is of greater general importance is a longstanding unresolved question in evolutionary genetics. We report mutational variances (VM) for 19 traits related to the first mitotic cell division in Caenorhabditis elegans and compare them to the standing genetic variances (VG) for the same suite of traits in a worldwide collection C. elegans Two robust conclusions emerge. First, the mutational process is highly repeatable: The correlation between VM in two independent sets of mutation accumulation lines is ∼0.9. Second, VM for a trait is a good predictor of VG for that trait: The correlation between VM and VG is ∼0.9. This result is predicted for a population at mutation-selection balance; it is not predicted if balancing selection plays a primary role in maintaining genetic variation.
authors.affiliation: School of Engineering and Applied Sciences, Department of Molecular and Cellular Biology, FAS Center for Systems Biology, Harvard University, Cambridge, Massachusetts 02138.
authors.forename: Reza
authors.initials: R
authors.lastname: Farhadifar
authors.affiliation: Department of Biology, University of Florida, Gainesville, Florida 32611.
authors.forename: José Miguel
authors.initials: JM
authors.lastname: Ponciano
authors.affiliation: Department of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208.
authors.forename: Erik C
authors.identifier: 0000-0003-0229-9651
authors.initials: EC
authors.lastname: Andersen
authors.affiliation: School of Engineering and Applied Sciences, Department of Molecular and Cellular Biology, FAS Center for Systems Biology, Harvard University, Cambridge, Massachusetts 02138.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Needleman
authors.affiliation: Department of Biology, University of Florida, Gainesville, Florida 32611 University of Florida Genetics Institute, University of Florida, Gainesville, Florida 32611 cbaer@ufl.edu.
authors.forename: Charles F
authors.initials: CF
authors.lastname: Baer
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics*; D014644:Genetic Variation; D008957:Models, Genetic; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D012641:Selection, Genetic / Q000235:genetics*; D008941:Spindle Apparatus / Q000235:genetics*
keywords: mutation accumulation; mutational robustness; mutational variance; mutation–selection balance; persistence time