Discrimination between Holstein-derived milk and pure Jersey dairy products via analysis of the MC1R gene

摘要

The majority of dairy cows in Japan are Holstein cows. Milk items containing only milk from Jersey cows are sold at a premium price. Therefore, it is important to keep Holstein milk from contaminating the milk labeled as pure Jersey milk to maintain brand value. Here, genetic testing was conducted on packaged milk items. Polymorphisms of the melanocortin-1 receptor (MCJR) gene, which controls variations in coat color, were assayed in addition to the frequencies of MCIR alleles in Holstein and Jersey cows in Japan. In Holstein cows, the frequency of the E-D allele was 0.876, but this allele is absent in Jersey cows. Thus, detection of the E-D allele clearly indicates the presence of Holstein DNA. This DNA-based test was also useful in testing sterilized milk products. The results of the DNA-based test show that pure Jersey milk can be easily distinguished from Holstein milk.