The book of abstracts is available. - Poznań

14 th QTL-MAS Workshop, Poznań University of Life Sciences, Poland 2010Genome wide effects of divergent selection for body weight in chickensAnna M. Johansson 1* , Mats E. Pettersson 1 , Paul B. Siegel 2 , Örjan Carlborg 11 Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Box 7023, S-75007 Uppsala, Sweden2 Virginia Polytechnic Institute and State University, Department of Animal and Poultry Sciences, Blacksburg,VA 24061-0306, USA*Presenting author: Anna Johansson, email: Anna.Johansson@hgen.slu.seTo understand the genetic mechanisms leading to phenotypic differentiation, it is important toidentify regions in a genome that are under selection. Here, we perform a genome wide scanusing a 60k SNP chip in two chicken lines from a single trait selection experiment, where 40generations of selection have resulted in a nine-fold difference in body weight. We analysedindividuals after 40 and 50 generations of selection in both the high body weight line and thelow body weight line. We show that the effect of selection is as dramatic on the genome as onthe phenotype. More than 60 regions were identified where selection has fixed alternativealleles in the two lines. Many more regions with highly significant large allele frequencydifferences were present all across the genome. Another 10 regions displayed strong evidencefor ongoing selection during the last 10 generations.28