title: The prion protein gene polymorphisms associated with bovine spongiform encephalopathy susceptibility differ significantly between cattle and buffalo.
abstract: Prion protein, encoded by the prion protein gene (PRNP), plays a crucial role in the pathogenesis of transmissible spongiform encephalopathies (TSEs). Several polymorphisms within the PRNP are known to be associated with influencing bovine spongiform encephalopathy (BSE) susceptibility in cattle, namely two insertion/deletion (indel) polymorphisms (a 23-bp indel in the putative promoter and a 12-bp indel in intron 1), the number of octapeptide repeats (octarepeats) present in coding sequence (CDS) and amino acid polymorphisms. The domestic buffaloes, Bubalus bubalis, are a ruminant involved in various aspects of agriculture. It is of interest to ask whether the PRNP polymorphisms differ between cattle and buffalo. In this study, we analyzed the previously reported polymorphisms associated with BSE susceptibility in Chinese buffalo breeds, and compared these polymorphisms in cattle with BSE, healthy cattle and buffalo by pooling data from the literature. Our analysis revealed three significant findings in buffalo: 1) extraordinarily low deletion allele frequencies of the 23- and 12-bp indel polymorphisms; 2) significantly low allelic frequencies of six octarepeats in CDS and 3) the presence of S4R, A16V, P54S, G108S, V123M, S154N and F257L substitutions in buffalo CDSs. Sequence alignments comparing the buffalo coding sequence to other species were analyzed using the McDonald-Kreitman test to reveal five groups (Bison bonasus, Bos indicus, Bos gaurus, Boselaphus tragocamelus, Syncerus caffer caffer) with significantly divergent non-synonymous substitutions from buffalo, suggesting potential divergence of buffalo PRNP and others. To the best of our knowledge this is the first study of PRNP polymorphisms associated with BSE susceptibility in Chinese buffalo. Our findings have provided evidence that buffaloes have a unique genetic background in the PRNP gene in comparison with cattle.
authors: Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China.
authors: Hui
authors: H
authors: Zhao
authors: Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China.
authors: Yanli
authors: Y
authors: Du
authors: State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China.
authors: Shunmei
authors: S
authors: Chen
authors: Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China.
authors: Lili
authors: L
authors: Qing
authors: Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China.
authors: Xiaoyan
authors: X
authors: Wang
authors: State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China.
authors: Jingfei
authors: J
authors: Huang
authors: State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China. Electronic address: wudongdong@mail.kiz.ac.cn.
authors: Dongdong
authors: D
authors: Wu
authors: Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China; State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China. Electronic address: zhangyp@mail.kiz.ac.cn.
authors: Yaping
authors: Y
authors: Zhang
mesh_terms: D000483:Alleles; D019943:Amino Acid Substitution; D000818:Animals; D002020:Buffaloes; D002417:Cattle; D004198:Disease Susceptibility; D016643:Encephalopathy, Bovine Spongiform / Q000821:virology*; D019143:Evolution, Molecular; D005787:Gene Frequency; D005838:Genotype; D006239:Haplotypes; D054643:INDEL Mutation; D016366:Open Reading Frames; D010802:Phylogeny; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D011328:Prions / Q000235:genetics*; D020080:Tandem Repeat Sequences
chemical_list: D011328:Prions
keywords: BSE; Buffalo; Divergence; Genetic differences; PRNP; Polymorphisms