The prevention of transmissible spongiform encephalopathy (TSE) in humans and animals has become an important element of safe food production. Part of the studies connected with this problem concentrate on the search for potential markers of the susceptibility or resistance to bovine spongiform encephalopathy (BSE). The present report presents a characteristic of the bovine prion protein (PRNP) gene polymorphism within the population of european bison and two endemic cattle breeds – Polish Red (PR) and Polish Whitebacked (PWb), the latter two included in a genetic resources conservation programme.European bison appeared monomorphic as regards PRNP what was reflected by the presence of only one genotype – PRNP 6/6. In the northern (lowland) subpopulation of PR the frequency of PRNP 6/6 and PRNP 6/5 genotypes was 0.926 and 0.074, respectively. In the PR southern (sub-montaneous) subpopulation the share of PRNP 6/5 and PRNP 5/5 was 0.214 and 0.049. In the PWb cattle the frequency of PRNP 6/6 was 0.628, that of PRNP 6/5 – 0.321, and of PRNP 5/5 – 0.051.