Abstract: Methods and compositions are provided for objectively identifying: i) bovine animals having the genetic potential to produce beef that is marbled or tender, and ii) bovine carcasses whose beef is marbled or tender. The methods comprise extracting DNA from a sample obtained from a bovine animal or carcass, assaying for the presence of a DNA comprising a sequence, referred to hereinafter as a “genetic marker”, in the DNA sample. In one aspect, the genetic marker is a marker of marbling, and comprises the sequence set forth in SEQ ID NO. 1. In another aspect, the genetic marker is a marker of tenderness, and comprises the sequence set forth in SEQ ID NO. 2, SEQ ID NO. 3, SEQ ID NO. 4 or combinations thereof. The compositions include primers that amplify markers of marbled or tender beef present in bovine animal or carcass genomes and hybridization probes to detect marbling or tenderness markers.

Abstract: Methods for identifying cattle and beef carcasses that have markers of beef tenderness are provided The methods comprise extracting DNA from a sample obtained from a bovine animal or beef carcass, amplifying the extracted DNA using a primer referred to hereinafter as the “CSTN” primer and low stringency polymerase chain reaction (PCR) conditions to provide a pool of PCR products, and then assaying the pool for the presence or absence of a PCR product of approximately 350 base pairs, a PCR product of approximately 625 base pairs, a PCR product of approximately 675 base pairs, a PCR product of approximately 1450 base pairs, or combinations thereof. The CSTN primer is a single stranded oligonucleotide of from 8 to 12 nucleotides and having the sequence 5′ CGGGCAGG-3′, SEQ ID NO:1. Methods for identifying cattle and carcasses that have markers of beef marbling are also provided.