NR AMJZ
AU Westaway,D.; Zuliani,V.; Cooper,C.M.; Da Costa,M.M.; Neuman,S.; Jenny,A.L.; Detwiler,L.; Prusiner,S.B.
TI Homozygosity for prion protein alleles encoding glutamine-171 renders sheep susceptible to natural scrapie
QU Genes and Development 1994 Apr 15; 8(8): 959-69
PT journal article
AB Natural scrapie has been viewed both as a recessive trait and as a contagious disease modulated by a host locus. To address this conundrum, we determined the structure of the sheep prion protein (PrP) gene, which contains three exons and extends over 20 kb of DNA. In the United States 86.4% of scrapie cases occur in Suffolk sheep, and within this breed 49 +/- 6% (+/- S.D., n = 69) of healthy animals carry one or more PrP alleles encoding Arg (R)-171. Four scrapie-affected sheep were homozygous for wild-type PrP open reading frames encoding the alternative Gln (Q)-171 allele. Analysis of additional cases revealed that all were Q/Q-171 homozygotes (n = 31), yielding a probability of 0.000004 that PrP genotype is unrelated to susceptibility. These data imply that homozygosity for Q-171 codons is necessary but not sufficient for the development of natural scrapie, echo reports of recessive manifestation, and parallel over-representation of PRNP codon 129 homozygotes in Creutzfeldt-Jakob disease of humans. Whereas progress has been substantial regarding experimental scrapie in rodents, the occurrence and spread of disease in flocks of sheep has remained enigmatic. Appreciation of the relationship between codon 171 genotype and susceptibility may help define the molecular basis of natural scrapie.
IN Das natürliche Scrapie ist eine ansteckende Krankheit mit einer anscheinend rezessiv vererbten Empfänglichkeit. Beim Schaf erstreckt sich das Prionproteingen über 20.000 Basen und enthält 3 Exons. In den Vereinigten Staaten von Amerika betreffen 86,4% der Scrapiefälle Suffolk Schafe. Unter den gesunden Tieren dieser offenbar besonders Scrapie-empfänglichen Rasse besitzt die Hälfte mindestens ein mutiertes Allel Prionproteingen, das ein Prionprotein mit einem Arginin anstatt eines Glutamins an der Position 171 kodiert. Von 31 daraufhin untersuchten an Scrapie erkrankten Schafen waren alle bezüglich der Aminosäure Glutamin-171 homozygot.
MH Alleles; Amino Acid Sequence; Animal; Base Sequence; Cloning, Molecular; Exons/genetics; Female; Genetic Predisposition to Disease; Glutamine/genetics; Homozygote; Male; Models, Genetic; Molecular Sequence Data; Polymorphism (Genetics); PrPsc Proteins/*genetics; Promoter Regions (Genetics)/genetics; Scrapie/epidemiology/*etiology/*genetics/prevention & control; Sequence Analysis, DNA; Sheep; Species Specificity; Support, Non-U.S. Gov't; Support, U.S. Gov't, Non-P.H.S.; Support, U.S. Gov't, P.H.S.; United States/epidemiology
AD Department of Neurology, University of California, San Francisco 94143.
SP englisch
PO USA