Etiological and molecular genetic surveillance of scrapie in Mongolia

蒙古羊痒病病原学和分子遗传学监测

• 批准号: 12575030
• 负责人: HORIUCHI Motohiro
• 金额: $ 7.23万
• 依托单位: Obihiro University of Agriculture and Veterinary Medicine
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12575030/
• 关键词: prion; scrapie; PrP; Mongolia; Genotype; PCR; BSE; 羊プリオン蛋白遺伝子; モンゴル産羊; 疫学調査; プリオン蛋白遺伝子型; モンゴル羊

Mongolia has a far long history for sheep-farming and is now farming over twelve million sheep. In the future, Mongolia has a potential for the major provider of livestock products among the world. Thus surveillance of prion diseases in animal in Mongolia will provide important information to evaluate the safety of livestock products in the country. During the research term, we visit to central, west, and east part of Mongolia, we did not get a positive indication on the existence of scrapie-suspected sheep in hearing. We also checked PrPSc in the medulla oblongata from sheep showed neurological symptoms, but all were negative for PrPSc.In order to investigate the diversity of PrP gene of sheep in Mongolia, we collected a total of 470 venous blood samples from 9 different breeds (Khalkh, Yeroo, Orkhon, Khangai, Sartuul, Govi-altai, Bayad, Darhad, and Symber-Karakul) and purified genomic DNA. PrP genotype (amino acid type) was determined by direct sequencing of PCR-amplified fragment corresponding to PrP open reading frame. With regard to PrP genotype at codon 171 determining susceptibility to scrapie, sheep carrying 171-Gln/Gln genotype that is associated with the susceptibility to scrape, varied from 58 to 97% among the breeds. Sheep carrying 171-Arg/Arg or 171-Arg/Gln genotype that confers resistance to scrapie infection were less abundant, especially only a small percentage of sheep possessed homozygous for 171-Arg alle. These results indicate sheep in Mongolia is composed rather of scrapie-susceptible population, so continuous surveillance as well as preventive measures against prion-infected animal are important to evaluate the risk of prion disease. These results are also useful for performing a selective breeding program that produce scrapie-resistant flock.

蒙古的养羊历史悠久，现在养着1200多万只羊。未来，蒙古有潜力成为世界上主要的畜产品供应国。因此，对蒙古动物中朊病毒疾病的监测将为评价该国畜产品的安全性提供重要信息。在研究期间，我们走访了蒙古中部、西部和东部地区，在听力上没有得到疑似羊瘙痒病存在的积极迹象。我们还检查了绵羊延髓中的PrPSc，显示神经症状，但所有的PrPSc均为阴性。为了研究蒙古绵羊PrP基因的多样性，我们采集了9个不同品种（Khalkh、Yeroo、Orkhon、Khangai、Sartuul、govis -altai、Bayad、Darhad和Symber-Karakul）共470份静脉血样本，并纯化了基因组DNA。通过对PrP开放阅读框对应的pcr扩增片段直接测序确定PrP基因型（氨基酸型）。关于决定痒病易感性的密码子171上的PrP基因型，携带与痒病易感性相关的171-Gln/Gln基因型的绵羊在不同品种之间的差异从58%到97%不等。携带171-Arg/Arg或171-Arg/Gln基因型的绵羊数量较少，特别是携带171-Arg等位基因纯合子的绵羊比例较小。这些结果表明，蒙古羊属于羊痒病易感人群，因此对感染朊病毒的动物采取持续监测和预防措施对评估朊病毒疾病的风险具有重要意义。这些结果也有助于进行选择性育种计划，以产生抗痒病的羊群。

项目成果

Gombojav, A.et al.: "Susceptibility of Transgenic Mice Expressing Chimeric Sheep, Bovine and Human PrP Genes to Sheep Scrapie"J.Vet.Med.Sci.. (in press). (2003)

Gombojav, A. 等人：“表达嵌合绵羊、牛和人 PrP 基因的转基因小鼠对绵羊痒病的敏感性”J.Vet.Med.Sci.（出版中）。

Horiuchi, M. et al.: "Biological and biochemical characterization of sheep scrapie in Japan"J.Clin.Microbiol. 40. 3421-3426 (2002)

Horiuchi, M. 等人：“日本羊痒病的生物学和生化特征”J.Clin.Microbiol。

Gombojav, A. et al.: "Susceptibility of Transgenic Mice Expressing Chimeric Sheep, Bovine and Human PrP Genes to Sheep Scrapie"J.Vet.Med.Sci.. (in press). (2003)

Gombojav, A. 等人：“表达嵌合羊、牛和人 PrP 基因的转基因小鼠对羊痒病的敏感性”J.Vet.Med.Sci.（出版中）。

Gombojav, A., et al.: "Susceptibility of transgenic mice expressing chimeric sheep, bovine and human PrP genes to sheep scrapie"J. Vet. Med. Sci.. in press.

Gombojav, A. 等人：“表达嵌合羊、牛和人 PrP 基因的转基因小鼠对羊瘙痒症的敏感性”J.

Gombojav, A. et al.: "Amino acid polymorphisms of PrP gene in Mongolian sheep"J.Vet.Med.Sci.. 65. 75-81 (2003)

Gombojav，A.等：“蒙古羊PrP基因的氨基酸多态性”J.Vet.Med.Sci..65.75-81(2003)