High-Resolution Melting Assay as a Tool for Identification of CSN3 Genotypes in Cattle Population

High-resolution melting (HRM) assay is a novel tool for polymorphism analysis. We describe here the application of high- resolution melting analysis for genotyping the main mutation of kappa-casein (CSN3) gene. The milk protein gene CSN3 is relevant in relation to milk production parameters and milk protein quality. The CSN3 gene encodes milk protein that is important for the structure and stability of casein micelles. The B allele of CSN3 is associated with higher milk protein content and milk quality. We tested 90 animals with known genotypes for CSN3 that were previously genotyped by PCR-RFLP and IEF methods, and then examined the sensitivity of mutation detection using quantitative PCR (qPCR) followed by HRM curve analysis. Known CSN3 variants were readily detectable using HRM assay. Thus, the qPCR-HRM assay is a sensitive in-tube methodology that allowed the rapid and sensitive identification of CSN3 genotypes. The results demonstrate that qPCR-HRM method is a fast, simple and reliable assay for CSN3 allele detection