Development of discrimination markers between Japanese domestic and imported beef

In the meat industry, correct labeling of beef origins or breed is required to assure quality and safety. This paper describes the development of discrimination markers between Japanese domestic and imported beef from the United States (US) and Australia (AUS) based on a bovine 50K single nucleotide polymorphism (SNP) array using a total of 110 samples: Japanese Black (n = 50), Japanese Holstein (n = 50) and US cattle (n = 10). Genotyping information revealed 1081 SNPs as candidate markers that were polymorphic only in US cattle. The genotyping results by PCR-restriction length polymorphism in Japanese Black (n = 300) and Holstein cattle (n = 146) revealed that 11 SNPs had alleles specific to US cattle. Their allelic frequencies in US cattle (n = 108) ranged from 0.097 to 0.250 with an average of 0.178 and the combined identification probability of US cattle was 0.987. In addition, we also verified the applicability of these US-specific markers to AUS cattle. Their allelic frequencies in AUS cattle (n = 280) ranged from 0.063 to 0.224 with an average of 0.137 and the combined identification probability of AUS cattle was 0.963. In conclusion, a set of these markers could be useful for discriminating between Japanese domestic and imported beef and would contribute to identify origins and prevent falsified labeling of beef.