NR AWKQ
AU Moreno,C.R.; Laurent,P.; Cazeau,G.; Goudarzi,K.; Andreoletti,O.; Chadi,S.; Elsen,J.M.; Calavas,D.
TI Resistance to atypical scrapie linked to codons 136, 141, 154, 171 of Prnp gene in France
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Poster sessions GEN-19
PT Konferenz-Poster
AB In sheep, scrapie disease is genetically controlled by alleles of the PRNP gene at codons 136, 154 and 171. After the discovery in 1998, in Norway of a specific strain (nor98), new atypical cases were found all over Europe. Amongst the specificity of the Norwegian cases, a large proportion of A136H154Q171 and A136F141R154Q171 allele carriers was demonstrated. In France, 54 atypical cases were detected by active surveillance so far. The aim of this study is to classify PrP genotypes at codons 136, 141, 154, 171 for their relative susceptibility to atypical scrapie. We proposed to explore PrP polymorphisms in atypical cases and in a 'control' population. For atypical scrapie cases, PrP genotypes at codons, 136, 141, 154 and 171 have been identified after direct sequencing of genomic DNA. The control population is composed by two data sets. Data set 1 was obtained in 2002 from 100 rams per breed sampled in French breeding centres. A RFLP-PCR technique has been performed to genotype codons 136, 154 and 171. Four alleles were detected ARR, AHQ, ARQ/H and VRQ. The allele ARH was confused with the allele ARQ. Data set 2 was established in 2006 using stocked genomic DNA of ARQ/H-ARQ/H rams born in 2002 and 2003. Animals have been sampled from breeding centres and nearly 100 rams per breed have been studied. PrP polymorphisms at codons, 136, 141, 154 and 171 of these rams have been analysed after direct sequencing. Using both data sets, frequencies of ARR, AHQ, VRQ, AFRQ, ALRQ and ARH alleles have been calculated within breed. The within breed frequencies were weighted by the breed size to give a representation of the global allele frequencies at the control population level. Our data confirmed a strong association of the AHQ and AFRQ alleles with the susceptibility to atypical scrapie. In accordance with the Norwegians, the AHQ appears less at risk than the AFRQ. The ARR, ARH and VRQ seem to confer some slight, susceptibility relative to the ALRQ.
AD C.R. Moreno, J.M. Elsen: INRA, Station d'Amélioration Génétique des Animaux, 31326 Castanet-Tolosan, France; P. Laurent, K. Goudarzi, S. Chadi: INRA Laboratoire de Génétique Bioch. et de Cytogénétique, 78252 Jouy-en-Josas, France; O. Andréoletti: UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France; G. Cazeau, D. Calavas: AFSSA-Lyon, Unité Epidémiologie, 31 Avenue Tony Garnier, 69364 Lyon Cedex 07, France. E-mail: moreno@toulouse.inra.fr
SP englisch
PO Italien