Different allelic effects of the codons 136 and 171 of the prion protein gene in sheep with natural scrapie.
Different allelic effects of the codons 136 and 171 of the prion protein gene in sheep with natural scrapie.
复制标题
朊病毒蛋白基因密码子136和171在患有天然瘙痒症的绵羊中的不同等位基因效应。
作者：
C. Clouscard;P. Beaudry;Jean;David J. Milan;M. Dussaucy;C. Bounneau;François Schelcher;J. Chatelain;Jean;Jean
瘙痒病是一种自然发生在绵羊身上的可传播的中枢神经系统退行性疾病。它属于也影响人类的普恩病毒疾病组，在这种疾病中，宿主编码的普恩蛋白(PrP)的异常亚型在大脑中积累，导致神经元死亡。绵羊PrP基因在第136、154和171位有三个主要的多态。在包括罗曼诺夫在内的几个品种中，绵羊PrP基因第136位密码子的二态与对天然瘙痒病的易感性/抗药性之间存在很强的关联。然而，这种二型性并不是在所有受瘙痒病影响的品种中都能找到。我们比较了从地方病感染的羊群中获得的拉考纳绵羊与表面上健康的绵羊的PrP基因分型。密码子171的第三个变异也被证明。将结果与口服线虫寄生虫攻击的单一罗曼诺夫实验羊群的结果进行了比较，在该实验羊群中突然出现了瘙痒病，导致80%的绵羊死亡。我们提出的证据表明，即使在不同的流行病学环境中，控制绵羊对自然瘙痒病的易感性/抗药性的主要遗传因素是PrP基因的密码子171。我们还认为，136密码子的等位基因效应的修饰可以发生在感染严重的动物身上。
Scrapie is a transmissible degenerative disease of the central nervous system occurring naturally in sheep. It belongs to the group of prion diseases also affecting man in which an abnormal isoform of the host-encoded prion protein (PrP) accumulating in the brain is responsible for neuronal death. Three main polymorphisms have been described in the sheep PrP gene, at positions 136, 154 and 171. A strong association between susceptibility/resistance to natural scrapie and a dimorphism at codon 136 of the ovine PrP gene has been reported in several breeds, including Romanov. This dimorphism, however, is not found in all scrapie-affected breeds. We have compared the PrP genotypes of Lacaune sheep obtained from enzootically affected flocks with those of apparently healthy sheep. A third variant at codon 171 was also evidenced. The results were compared with those obtained in a single experimental Romanov flock orally challenged with nematode parasites in which scrapie suddenly appeared and killed 80% of the sheep. We present evidence that, even in different epizootological circumstances, the major genetic factor controlling the susceptibility/resistance to natural scrapie in sheep, is represented by codon 171 genotype of the PrP gene. We also suggest that a modification of the allelic effects of codon 136 can occur in heavily infected animals.
影响因子：
10.5
作者：
D. Westaway;V. Zuliani;C. Cooper;M. Da Costa;S. Neuman;A L Jenny;L. Detwiler;S. B. Prusiner
通讯作者：
D. Westaway;V. Zuliani;C. Cooper;M. Da Costa;S. Neuman;A L Jenny;L. Detwiler;S. B. Prusiner