title: Protective effect of the T112 PrP variant in sheep challenged with bovine spongiform encephalopathy.
abstract: Sheep with an ARQ/ARQ PRNP genotype at codon positions 136/154/171 are highly susceptible to experimental infection with bovine spongiform encephalopathy (BSE). However, a number of sheep challenged orally or intracerebrally with BSE were clinically asymptomatic and found to survive or were diagnosed as BSE-negative when culled. Sequencing of the full PRNP gene open reading frame of BSE-susceptible and -resistant sheep indicated that, in the majority of Suffolk sheep, resistance was associated with an M112T PRNP variant (TARQ allele). A high proportion (47 of 49; 96%) of BSE-challenged wild-type (MARQ/MARQ) Suffolk sheep were BSE-infected, whereas none of the 20 sheep with at least one TARQ allele succumbed to BSE. Thirteen TARQ-carrying sheep challenged with BSE are still alive and some have survival periods equivalent to, or greater than, reported incubation periods of BSE in ARR/ARR and VRQ/VRQ sheep.
authors: Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency (VLA Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
authors: G C
authors: GC
authors: Saunders
authors: INRA, UR1282, Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France.
authors: I
authors: I
authors: Lantier
authors: Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency (VLA Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
authors: S
authors: S
authors: Cawthraw
authors: INRA, UR1282, Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France.
authors: P
authors: P
authors: Berthon
authors: Pathology Department, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
authors: S J
authors: SJ
authors: Moore
authors: CERA, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
authors: M E
authors: ME
authors: Arnold
authors: Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency (VLA Weybridge), New Haw, Addlestone, Surrey KT15 3NB, UK.
authors: O
authors: O
authors: Windl
authors: Pathology Department, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
authors: M M
authors: MM
authors: Simmons
authors: UMR INRA-ENVT, Interactions Hôtes-Agents Pathogènes, Ecole Vétérinaire de Toulouse, F-310761 Toulouse, France.
authors: O
authors: O
authors: Andréoletti
authors: Pathology Department, VLA Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
authors: S
authors: S
authors: Bellworthy
authors: INRA, UR1282, Infectiologie Animale et Santé Publique, F-37380 Nouzilly, France.
authors: F
authors: F
authors: Lantier
mesh_terms: D000818:Animals; D002417:Cattle; D016643:Encephalopathy, Bovine Spongiform / Q000235:genetics / Q000276:immunology / Q000635:transmission*; D020022:Genetic Predisposition to Disease; D005838:Genotype; D011328:Prions / Q000276:immunology*; D012756:Sheep; D012757:Sheep Diseases / Q000235:genetics / Q000276:immunology*
chemical_list: D011328:Prions