POLYMORPHISM ANALYSIS OF THE PRION GENE IN BSE-AFFECTED AND UNAFFECTED CATTLE

Polymerase chain reaction (PCR) primers designed to amplify the octape ptide repeat region of the bovine prion gene were used to test the ass ociation of genotypes with bovine spongiform encephalitis (BSE) in 56 BSE-affected and 177 unaffected animals. Three alleles (A,B,C) were de tected as single-strand conformation polymorphisms (SSCPs) and two all eles (1,2-representing six or five copies of the octapeptide repeat re spectively) were detected as amplified double-strand fragment length p olymorphisms (AMFLPs). Observed genotypes of SSCPs and AMFLPs were ana lysed by X-square. The SSCP genotypes of nuclear family members of ani mals with BSE and BSE-affected animals were different (P < 0.001, P < 0.01) from unrelated animals of the same breed without BSE. No genotyp ic differences were found between the BSE-affected animals and their r elatives (P > 0.469). No AMFLP genotypic differences were detected bet ween BSE-affected animals, their relatives, unrelated animals of the s ame breed or animals of different breeds (P > 0.05). These data sugges t that BSE-affected animals and their relatives are more likely to hav e the AA SSCP genotype than unrelated animals of the same breed or ani mals of different breeds.