Scrapie Genotyping

The USDA APHIS VS intends to acquire the services of two or more laboratories to perform genetic testing of the encoded amino acid at codons 136 and 171 in sheep and codons 146 and 222 for goats within the gene controlling the structure of the prion protein. Codon 171 appears to be the principal determinant of scrapie resistance for U.S. sheep genotypes and scrapie strains. Most of the genotype testing is expected to involve this codon. Prior to consideration for the provision of these contract services, each candidate laboratory must comply with the regulations and policies set forth in 9 CFR 54.11 and USDA APHIS VS Memorandum 557.6 which outline the steps needed for laboratory approval to conduct these official genotype tests. The information in this memorandum is presented as an attachment noted in Section J. Laboratories that are currently approved by APHIS to conduct official genotyping for scrapie resistance for sheep do not need to re-submit the entire application package if only testing sheep. In such cases, those laboratories need to indicate their desire to continue as approved laboratories, submit any information related to Section C.4 in this document, and complete and submit their respective pricing matrices. If offering to genotype goats the application for approval to test goats for scrapie susceptibility must be submitted prior to award and the approval process successfully completed prior to task orders being issued for goat genotyping. We currently expect the goat check test panel as described in C.4 to be available from the National Veterinary Services Laboratories, to laboratories seeking approval in December 2018.