Microsatellite polymorphisms in the ovine prion protein gene in relation to PRP genotypes

The aims of the study were to detect the polymorphisms of three microsatellite sites: S11, S15, and S24 in the ovine PRNP and to asses their relationship with prion protein (PrP) genotypes in three sheep breeds. To identify 15 PrP genotypes based on polymorphisms at codons 136, 154, and 171, PCR-RFLP analyses were applied. The microsatellite sites were amplified. For each microsatellite two or three alleles per site in homoand heterozygotic combinations were observed. In the group of scrapie resistant sheep (NSP1), the genotype 152/152 bp of the S11 microsatellite, 179/179 bp of S15, and 144/144 bp of S24 occurred with the highest frequencies. The results of Fisher’s exact test showed that associations between PrP genotypes and microsatellite alleles and genotypes in the PRNP were statistically significant (P<0.001). In conclusion, the investigated microsatellite sites may be used as additional genetic markers in prion protein gene variability studies in sheep.