Survey on scrapie in Japanese : detection of PrP^<Sc> and studies on the distribution of the PrP genotypes in sheep.

1.绵羊PrP基因的限制性片段长度多态性(RFLP)：为研究绵羊PrP基因的RFLP类型，以EcoRI和HindIII限制性内切酶及绵羊PrP编码区为探针，对日本不同地区绵羊组织的染色体DNA进行了分析。将绵羊分为6个类型。类型I至类型III与英国报告的类型相对应。近一半的瘙痒病绵羊属于I型，而II型的出现频率很低。各类型在日本不同地区的分布表现出一定的差异。日本羊瘙痒病调查：为了解日本羊瘙痒病的发病情况，对来自日本各地的197只绵羊的脑、脾和淋巴结进行了PrP^&lt；Sc&gt；从北海道采集的16只绵羊和从其他地区采集的2只绵羊中检出PRP^&lt；SC&gt；然而，这两只羊也是在北海道饲养的。这些发现表明，在日本，羊痒病的污染仅限于北海道生产的绵羊。

1. Restriction fragment length polymorphism (RFLP) on the sheep-PrP gene : To investigate the RFLP types on the PrP-gene, chromosomal DNAs from sheep tissues collected from various districts in Japan were analyzed using restriction endonucleases EcoRI and HindIII and the coding region of sheep PrP as a probe. Sheep were classified into 6 types. Types I to III corresponded to the types reported in England. Nearly half of the scrapie sheep belonged to type I and the frequency of type II in scrapie sheep was low. Distribution of the types in different parts of Japan showed some variations.2. Survey of scrapie infected sheep in Japan : To survey the incidence of scrapie infection in Japan, detection of PrP^<Sc> in a total of 197 sheep brains, spleens and lymph nodes obtained from various districts in Japan was carried out. PrP^<Sc> was detected in 16 sheep collected in Hokkaido and in 2 obtained from other districts. However, these two sheep had also been produced in Hokkaido. These findings suggest that contamination with scrapie in Japan is restricted to sheep produced in Hokkaido.