The present results suggest that meat tenderness in Nellore cattle does not directly depend on the expression of the CAPN1 and CAPN2 genes, but is associated with the expression of other genes such as CAST2, HSP90AA1, DNAJA1 and HSPB1.
Nine were down-regulated in the same meats, but only DNAJA1 [the results relating to DNAJA1 and its relationship with tenderness have been patented (Genomic marker for meat tenderness; Patent EP06300943.5, September 12, 2006)], which encodes a heat shock protein, showed a strong negative correlation with tenderness that alone explained 63% of its variability.