title: Mapping and validation of a major QTL affecting resistance to pancreas disease (salmonid alphavirus) in Atlantic salmon (Salmo salar).
abstract: Pancreas disease (PD), caused by a salmonid alphavirus (SAV), has a large negative economic and animal welfare impact on Atlantic salmon aquaculture. Evidence for genetic variation in host resistance to this disease has been reported, suggesting that selective breeding may potentially form an important component of disease control. The aim of this study was to explore the genetic architecture of resistance to PD, using survival data collected from two unrelated populations of Atlantic salmon; one challenged with SAV as fry in freshwater (POP 1) and one challenged with SAV as post-smolts in sea water (POP 2). Analyses of the binary survival data revealed a moderate-to-high heritability for host resistance to PD in both populations (fry POP 1 h(2)~0.5; post-smolt POP 2 h(2)~0.4). Subsets of both populations were genotyped for single nucleotide polymorphism markers, and six putative resistance quantitative trait loci (QTL) were identified. One of these QTL was mapped to the same location on chromosome 3 in both populations, reaching chromosome-wide significance in both the sire- and dam-based analyses in POP 1, and genome-wide significance in a combined analysis in POP 2. This independently verified QTL explains a significant proportion of host genetic variation in resistance to PD in both populations, suggesting a common underlying mechanism for genetic resistance across lifecycle stages. Markers associated with this QTL are being incorporated into selective breeding programs to improve PD resistance.
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK.
authors.forename: S
authors.initials: S
authors.lastname: Gonen
authors.affiliation: Nofima, Ås, Norway.
authors.forename: M
authors.initials: M
authors.lastname: Baranski
authors.affiliation: Akvaforsk Genetics Center AS, Sunndalsøra, Norway.
authors.forename: I
authors.initials: I
authors.lastname: Thorland
authors.affiliation: Marine Harvest, Bergen, Norway.
authors.forename: A
authors.initials: A
authors.lastname: Norris
authors.affiliation: Department of Animal and Aquacultural Sciences and Centre for Integrative Genetics, Norwegian University of Life Sciences, Ås, Norway.
authors.forename: H
authors.initials: H
authors.lastname: Grove
authors.affiliation: Marine Harvest, Bergen, Norway.
authors.forename: P
authors.initials: P
authors.lastname: Arnesen
authors.affiliation: SalmoBreed AS, Bergen, Norway.
authors.forename: H
authors.initials: H
authors.lastname: Bakke
authors.affiliation: Department of Animal and Aquacultural Sciences and Centre for Integrative Genetics, Norwegian University of Life Sciences, Ås, Norway.
authors.forename: S
authors.initials: S
authors.lastname: Lien
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK.
authors.forename: S C
authors.initials: SC
authors.lastname: Bishop
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK.
authors.forename: R D
authors.initials: RD
authors.lastname: Houston
mesh_terms: D000524:Alphavirus; D000818:Animals; D002874:Chromosome Mapping; D060467:Disease Resistance / Q000235:genetics*; D005260:Female; D005393:Fish Diseases / Q000235:genetics* / Q000821:virology; D005828:Genetics, Population; D005838:Genotype; D040582:Inheritance Patterns; D008297:Male; D008957:Models, Genetic; D010182:Pancreatic Diseases / Q000235:genetics / Q000662:veterinary* / Q000821:virology; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D020317:Salmo salar / Q000235:genetics* / Q000821:virology