ASSOCIATION OF THE EXON 9 SINGLE-NUCLEOTIDE POLYMORPHISM OF CAPfli WITH BEEF TENDERNESS

摘要

Initial data analysis from both the University of Adelaide's Davies Cattle Gene Mapping and the New Zealand AgResearch Cattle Gene Mapping Projects showed a tenderness quantitative trait locus (QTL) on BTA29. Based on its function and location, the gene for micromolar calcium-activated neutral protease or calpain gene (CAPN1) was considered to be a strong positional candidate for the observed QTL effects. The objective of this study was to assess the association of a previously reported single nucleotide polymorphism (SNP) in Exon 9 of CAPN1 with the tenderness of M. longissimus dorsi (LD) and M. semitendinosus (ST) muscles in Bos taurus. The SNP (base 5709) causes the amino acid substitution of alanine for glycine in the u-calpain enzyme. Results demonstrated that the Exon 9 SNP was significantly associated with tenderness of both ST and LD muscles (PO.01). Animals with the GG genotype showed higher (P<0.01) shear force values compared with CC genotypes (15% and 11% on day 1 and 14% and 11% on day26 in LD and ST, respectively). The paternal allele encoding glycine at position 316 was associated with decreased meat tenderness relative to the allele encoding alanine at position 316. The equivalent maternal allele for CAPN1 Exon 9 was significantlyassociated with decreased tenderness of LD at four cook times and ST at day 1.