The survey of genetic susceptibility to bovine spongiform encephalopathy among Iranian native and Holstein cattle breeds

In recent years، the relationship between insertion and deletion (indel) polymorphisms in promoter region (23 bp) and intron 1 (12 bp) of PRNP gene (Prion protein coding gene) and their relationship to susceptibility of classical bovine spongiform encephalopathy (BSE) have been reported. Insertions of these two polymorphisms increase resistance to classical BSE، while the deletions of these two polymorphisms cause more susceptibility to classical BSE. In this study DNA of Iranian Holstein (n=50)، Golpayegani (n=62) and Sistani (n=60) was extracted by modified salting out method. The genes were amplified using specific primers and the genotypes were detected on polyacrylamide gels. Allelic data were tested by Exact Fisher test and genotypic and haplotypic data were tested using Chi-square test. The results showed that considering locus of three mentioned breeds were in Hardy-Weinberg equilibrium. The allelic، genotypic and haplotypic frequencies of the polymorphism of the mentioned genes were estimated in three Iranian cattle breeds and were compared among breeds under this study and the healthy and BSE-affected group of the German cattle (described by Sander et al.، 2004). According to the results of this study، if these two regions are the only regions affecting on the classical BSE، Golpayegani cattle have more resistant than healthy and BSE-affected of German cattle.