FORPRION

BAVARIAN RESEARCH ASSOCIATION PRIONS

LMU 15 BSE Genomics A

As an condition to make association studies between specific bovine PRNP DNA variants and a genetic disposition for BSE in cattle we genotyped 989 animals each for six PRNP-DNA markers. The animal material consists of 364 BSE affected , 311 BSE free Fleckvieh and 313 BSE free Braunvieh control animals. There exists no comparable study for these main Bavarian cattle races to day. From the genotyping results the allele and genotype frequencies are calculated. In the complete material of all 989 animals the haplotypes of the investigated PRNP region were deduced by the software programs SimWalk2 and PHASE 46. A coalezence based association mapping were applied to proof the possibility of an association between a specific PRNP haplotype and an increased susceptibility for BSE in Fleckvieh and Braunvieh cattles. Unless the case of an extreme competent calculation model ( application of Linux clusters each of 24 computers) there could be only small associations (below under a statistic significant level) between an increased BSE susceptibility and specific PRNP haplotypes determined. The QTLs for milk yield and ingredients 10-30 cM distant to the PRNP locus no selection effects to an increased BSE susceptibility could be established. The results demonstrated clearly there is no acceptable reason to involve PRNP haplotypes in the ongoing selection systems in Fleckvieh and Braunvieh cattles in Germany.