title: Whole-Genome Hitchhiking on an Organelle Mutation.
abstract: Strong selection on a beneficial mutation can cause a selective sweep, which fixes the mutation in the population and reduces the genetic variation in the region flanking the mutation [1-3]. These flanking regions have increased in frequency due to their physical association with the selected loci, a phenomenon called "genetic hitchhiking" [4]. Theoretically, selection could extend the hitchhiking to unlinked parts of the genome, to the point that selection on organelles affects nuclear genome diversity. Such indirect selective sweeps have never been observed in nature. Here we show that strong selection on a chloroplast gene in the wild plant species Arabidopsis thaliana has caused widespread and lasting hitchhiking of the whole nuclear genome. The selected allele spread more than 400 km along the British railway network, reshaping the genetic composition of local populations. This demonstrates that selection on organelle genomes can significantly reduce nuclear genetic diversity in natural populations. We expect that organelle-mediated genetic draft is a more common occurrence than previously realized and needs to be considered when studying genome evolution.
authors.affiliation: Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands; Horticulture and Production Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands; Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linne-Weg 10, 50829 Cologne, Germany. Electronic address: flood@mpipz.mpg.de.
authors.forename: Pádraic J
authors.initials: PJ
authors.lastname: Flood
authors.affiliation: Plant Production Systems, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands.
authors.forename: Joost
authors.initials: J
authors.lastname: van Heerwaarden
authors.affiliation: Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands.
authors.forename: Frank
authors.initials: F
authors.lastname: Becker
authors.affiliation: Rijk Zwaan R&D Fijnaart, Eerste Kruisweg, 4793 RS Fijnaart, the Netherlands.
authors.forename: C Bastiaan
authors.initials: CB
authors.lastname: de Snoo
authors.affiliation: Horticulture and Production Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Harbinson
authors.affiliation: Laboratory of Genetics, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, the Netherlands.
authors.forename: Mark G M
authors.initials: MG
authors.lastname: Aarts
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D061125:Genes, Chloroplast; D018745:Genome, Plant; D009154:Mutation; D015388:Organelles; D012641:Selection, Genetic