Acín Cristina, Martín-Burriel Inmaculada, Goldmann Wilfred, Lyahyai Jaber, Monzón Marta, Bolea Rosa, Smith Allister, Rodellar Clementina, Badiola Juan José, Zaragoza Pilar
National Reference Centre for Transmissible Spongiform Encephalopathies, Animal Pathology Department, Veterinary Faculty, C/Miguel Servet 177, 50013 Zaragoza, Spain.
Biochemical Genetics and Blood Groups Laboratory, University of Zaragoza, C/Miguel Servet 177, 50013 Zaragoza, Spain.
J Gen Virol. 2004 Jul;85(Pt 7):2103-2110. doi: 10.1099/vir.0.80047-0.
The Rasa Aragonesa sheep is the second most important Spanish breed after the Merino breed. Reported here is the prion protein (PrP) haplotype frequency distribution for scrapie-related codons (136, 154 and 171) and a sequencing study of the complete PrP gene open reading frame for this breed and six other closely related breeds. The study includes four scrapie-affected sheep flocks belonging to Rasa Aragonesa and Rasa Navarra breeds. Thirty-eight scrapie-affected sheep, 502 healthy sheep from scrapie-affected flocks and 905 sheep from a breed survey were genotyped. The most frequent PrP haplotype in both scrapie and healthy flocks was ARQ, which was found at significantly higher frequency in scrapie-affected sheep. The susceptibility-associated VRQ haplotype was found at low frequencies in six out of eight breeds, but was not present in the 38 scrapie-affected sheep. The resistance-associated ARR haplotype was found in all breeds except one (Ojinegra) at frequencies >or=14 %. Fourteen amino acid polymorphisms were detected in these Spanish sheep, including the known amino acid substitutions at codons 112, 136, 141, 143, 154, 171 and 176, and new polymorphisms at codons 101 (Q-->R), 151 (R-->G), 151 (R-->H), 172 (Y-->D) and 175 (Q-->E). Most of the novel polymorphic codons show frequencies lower than 5 %.
阿拉贡纳绵羊是西班牙继美利奴羊之后第二重要的品种。本文报道了该品种与瘙痒病相关密码子（136、154和171）的朊病毒蛋白（PrP）单倍型频率分布情况，以及对该品种和其他六个密切相关品种的完整PrP基因开放阅读框的测序研究。该研究包括四个受瘙痒病影响的绵羊群，分别属于阿拉贡纳和纳瓦拉品种。对38只受瘙痒病影响的绵羊、502只来自受瘙痒病影响羊群的健康绵羊以及905只来自品种调查的绵羊进行了基因分型。在瘙痒病和健康羊群中最常见的PrP单倍型是ARQ，在受瘙痒病影响的绵羊中其频率显著更高。与易感性相关的VRQ单倍型在八个品种中的六个品种中频率较低，但在38只受瘙痒病影响的绵羊中未出现。与抗性相关的ARR单倍型在除一个品种（奥希内格拉）外的所有品种中均有发现，频率≥14%。在这些西班牙绵羊中检测到14个氨基酸多态性，包括已知的密码子112、136、141、143、154、171和176处的氨基酸替换，以及密码子101（Q→R）、151（R→G）、151（R→H）、172（Y→D）和175（Q→E）处的新多态性。大多数新的多态密码子频率低于5%。
