Laegreid W W, Clawson M L, Heaton M P, Green B T, O'Rourke K I, Knowles D P
University of Illinois, Department of Pathobiology, 2001 S. Lincoln Ave., Urbana, IL 61802, USA.
J Virol. 2008 Oct;82(20):10318-20. doi: 10.1128/JVI.00710-08. Epub 2008 Jul 16.
Variation in the ovine prion protein amino acid sequence influences scrapie progression, with sheep homozygous for A(136)R(154)Q(171) considered susceptible. This study examined the association of survival time of scrapie-exposed ARQ sheep with variation elsewhere in the ovine prion gene. Four single nucleotide polymorphism alleles were associated with prolonged survival. One nonsynonymous allele (T112) was associated with an additional 687 days of survival for scrapie-exposed sheep compared to M112 sheep (odds ratio, 42.5; P = 0.00014). The only two sheep homozygous for T112 (TARQ) did not develop scrapie, suggesting that the allelic effect may be additive. These results provide evidence that TARQ sheep are genetically resistant to development of classical scrapie.
绵羊朊病毒蛋白氨基酸序列的变异会影响羊瘙痒病的病程进展，其中纯合子为A(136)R(154)Q(171)的绵羊被认为易感染。本研究检测了感染羊瘙痒病的ARQ绵羊的存活时间与绵羊朊病毒基因其他位点变异之间的关联。有四个单核苷酸多态性等位基因与存活时间延长有关。与M112绵羊相比，一个非同义等位基因（T112）与感染羊瘙痒病的绵羊的存活时间延长687天有关（优势比，42.5；P = 0.00014）。仅有的两只T112纯合子绵羊（TARQ）未发生羊瘙痒病，这表明等位基因效应可能具有累加性。这些结果证明TARQ绵羊对经典型羊瘙痒病的发生具有遗传抗性。
