title: MHC polymorphism and disease resistance in Atlantic salmon (Salmo salar); facing pathogens with single expressed major histocompatibility class I and class II loci.
abstract: Few studies have yet addressed the functional aspects of MHC molecules in fish. To lay the foundation for this, we evaluated the association between disease resistance and MHC class I and class II polymorphism in Atlantic salmon. Standardized disease challenge trials were performed on a semi-wild Atlantic salmon population with subsequent MHC typing and statistical analysis. The pathogens employed were infectious salmon anaemia virus (ISAV) causing infectious salmon anaemia and the Aeromonas salmonicida bacteria causing furunculosis. The material consisted of 1,182 Atlantic salmon from 33 families challenged with A. salmonicida and 1,031 Atlantic salmon from 25 families challenged with ISAV. We found highly significant associations between resistance towards infectious diseases caused by both pathogens and MH class I and class II polymorphism in Atlantic salmon. The observed associations were detected due to independently segregating MH class I and class II single loci, and inclusion of a large number of fish allowing an extensive statistical analysis.
authors.affiliation: Department of Morphology, Genetics and Aquatic Biology, Section of Genetics, Norwegian School of Veterinary Science, Ullevaalsveien 72, P.O. Box 8146 Dep., 0033 Oslo, Norway. Unni.Grimholt@veths.no
authors.forename: Unni
authors.initials: U
authors.lastname: Grimholt
authors.forename: Stig
authors.initials: S
authors.lastname: Larsen
authors.forename: Rolf
authors.initials: R
authors.lastname: Nordmo
authors.forename: Paul
authors.initials: P
authors.lastname: Midtlyng
authors.forename: Sissel
authors.initials: S
authors.lastname: Kjoeglum
authors.forename: Arne
authors.initials: A
authors.lastname: Storset
authors.forename: Solve
authors.initials: S
authors.lastname: Saebø
authors.forename: René J M
authors.initials: RJ
authors.lastname: Stet
mesh_terms: D000333:Aeromonas / Q000472:pathogenicity; D000483:Alleles; D000818:Animals; D005393:Fish Diseases / Q000235:genetics / Q000276:immunology; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D016905:Gram-Negative Bacterial Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary; D009975:Orthomyxoviridae / Q000472:pathogenicity; D009976:Orthomyxoviridae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary; D011110:Polymorphism, Genetic; D040641:Quantitative Trait Loci; D020317:Salmo salar / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology / Q000821:virology