title: The genetic architecture of the MHC class II region in British Texel sheep.
abstract: Understanding the structure of the major histocompatibility complex, especially the number and frequency of alleles, loci and haplotypes, is crucial for efficient investigation of the way in which the MHC influences susceptibility to disease. Nematode infection is one of the most important diseases suffered by sheep, and the class II region has been repeatedly associated with differences in susceptibility and resistance to infection. Texel sheep are widely used in many different countries and are relatively resistant to infection. This study determined the number and frequency of MHC class II genes in a small flock of Texel sheep. There were 18 alleles at DRB1, 9 alleles at DQA1, 13 alleles at DQB1, 8 alleles at DQA2 and 16 alleles at DQB2. Several haplotypes had no detectable gene products at DQA1, DQB1 or DQB2, and these were defined as null alleles. Despite the large numbers of alleles, there were only 21 distinct haplotypes in the population. The relatively small number of observed haplotypes will simplify finding disease associations because common haplotypes provide more statistical power but complicate the discrimination of causative mutations from linked marker loci.
authors.affiliation: Animal Medicine Department, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt.
authors.forename: Alsagher O A
authors.initials: AO
authors.lastname: Ali
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Garscube Campus, Bearsden Road, Glasgow, Scotland, G61 1QH, UK.
authors.forename: Abigail
authors.initials: A
authors.lastname: Stear
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Garscube Campus, Bearsden Road, Glasgow, Scotland, G61 1QH, UK.
authors.forename: Karen
authors.initials: K
authors.lastname: Fairlie-Clarke
authors.affiliation: Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
authors.forename: Gholamreza Nikbakht
authors.initials: GN
authors.lastname: Brujeni
authors.affiliation: Faculty of Veterinary Medicine, Universiti Putra Malaysia, UPM, 43400, Serdang, Selangor Darul Ehsan, Malaysia.
authors.forename: N Mahiza Md
authors.initials: NM
authors.lastname: Isa
authors.affiliation: Faculty of Veterinary Medicine, Universiti Putra Malaysia, UPM, 43400, Serdang, Selangor Darul Ehsan, Malaysia.
authors.forename: M Shahrom Bin
authors.initials: MS
authors.lastname: Salisi
authors.affiliation: Department of Parasitology, Institute of Zoology, Faculty of Biology, University of Warsaw, ul. Miecznikowa, 02-096, Warsaw, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Donskow-Łysoniewska
authors.affiliation: School of Biomedical Sciences, CHIRI Biosciences Research Precinct, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Groth
authors.affiliation: Bavarian State Research Center for Agriculture, Institute of Animal, Breeding, 85580, Grub, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Buitkamp
authors.affiliation: Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Garscube Campus, Bearsden Road, Glasgow, Scotland, G61 1QH, UK. m.stear@latrobe.edu.au.|Department of Animal, Plant and Soil Science, Agribio, La Trobe University, Bundoora, VIC, 3086, Australia. m.stear@latrobe.edu.au.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Stear
mesh_terms: D000483:Alleles; D000818:Animals; D005787:Gene Frequency; D005802:Genes, MHC Class II / Q000235:genetics*; D006680:HLA Antigens / Q000235:genetics*; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D012756:Sheep / Q000235:genetics*; D044465:White People / Q000235:genetics*
chemical_list: D006680:HLA Antigens
keywords: Class II region; Major histocompatibility complex; Polymorphism; Sheep; Texel breed