Bovine spongiform encephalopathy associated insertion/deletion polymorphisms of the prion protein gene in the four beef cattle breeds from North China

Abstract

Two insertion/deletion (indel) polymorphisms of the prion protein gene (PRNP), a 23-bp indel in the putative promoter region and a 12-bp indel within intron I, are associated with the susceptibility to bovine spongiform encephalopathy (BSE) in cattle. In the present study, the polymorphism frequencies of the two indels in four main beef cattle breeds (Hereford, Simmental, Black Angus, and Mongolian) from North China were studied. The results showed that the frequencies of deletion genotypes and alleles of 23- and 12-bp indels were lower, whereas the frequencies of insertion genotypes and alleles of the two indels were higher in Mongolian cattle than in the other three cattle breeds. In Mongolian cattle, the 23-bp insertion / 12-bp insertion was the major haplotype, whereas in Hereford, Simmental, and Black Angus cattle, the 23-bp deletion / 12-bp deletion was the major haplotype. These results demonstrated that Mongolian cattle could be more resistant to BSE, compared with the other three cattle breeds, because of its relatively low frequencies of deletion genotypes and alleles of 23- and 12-bp indel polymorphisms. Thus, this race could be important for selective breeding to improve resistance against BSE in this area.