| Abstract Detail
Recent Topics Posters Song, Bao-Hua [1], Windsor, Aaron J. [2], Ramos-Onsins, Sebastian [3], Schmid, Karl J [4], Schranz, M. Eric [5], Heidel, Andrew [6], Mitchell-Olds, Tom [2]. Low level of Linkage Disequilibrium and high population differentiation in predominantly inbreeding Arabidopsis wild relative − Boechera stricta. Genome-wide information about polymorphism, population structure and linkage disequilibrium (LD) is crucial for understanding genotypic-phenotypic association and mechanisms of adaptive evolution. However, most genome-wide studies have focused on model systems, with little data available for non-model plant species. In this study, we sequenced eighty-six mapped single copy nuclear loci (SCNL) for a sample of 46 accessions (one genotype per population) of Boechera stricta and two accessions of Boechera holboellii, both close wild relatives of Arabidopsis. The results of evolutionary analyses show that: average silent polymorphism in B. stricta is 0.004. Population structure and isolation by distance are evident in the species-level sampling in B. stricta. Three groups (WEST, NORTH and SOUTH) are identified by STRUCTURE analysis, PCA and distance based phylogeny analysis. The northern group is geographically located in Idaho and Montana, while the southern group is centered in Colorado. The western group is widely dispersed in the Western United States, is substantially differentiated from the rest of the species, and shows significant differences for morphological traits. Intra-locus LD decays rapidly in B. stricta, with mean r2 decreasing to 0.1 within 1kb, similar to that observed in the outcross Zea mays. However, estimated levels of LD in B. stricta are substantially higher after controlling for population structure. Also, there is little relationship between inter-locus LD and map distance in this species, as has been found in A. thaliana, indicating that genome-wide markers in this study are sufficiently far apart for recombination to have broken up most association. This is a comprehensive study for on-going association analysis and evolutionary functional genomic studies.
Log in to add this item to your schedule
1 - Duke University, Department of Biology,, PO Box 90338, Durham, NC, 27708, USA
2 - Duke University, Biology, Box 90338, Durham, NC, 27708, USA
3 - Universitat de Barcelona, Departament de Genètica, Diagonal 645, Barcelona, Spain
4 - Max Planck Institute for Chemical Ecology, Department of genetics and evolution, Hans-Knöll-Straße 8, Jena, 07745, Germany
5 - University of Amsterdam, Institute for Biodiversity and Ecosystem Dynamics, P.O. Box 94062, Amsterdam, 1090 GB, The Netherlands
6 - Fritz Lipmann Institute, Beutenbergstrasse 11, Jena, 07745, Germany
Keywords:
Boechera stricta
Polymorphism
population structure
Linkage disequilibrium
inbreeding
differentiation
Arabidopsis relatives.
Presentation Type: Recent Topics Poster
Session: P
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM
Number: P79027
Abstract ID:2673 |
