Détection fine de QTL de tendreté de la viande dans trois races allaitantes françaises

Without routine measurement of sensory meat quality traits , breeding companies wonder how to take advantage of the genetic variability of these traits at the molecular level. The projects “Qualvigene” and “Qualvigene + ABQV” were set in to find markers associated to beef quality therefore. A total of 1,059 Charolais, 1,219 Limousin and 947 Blond d’Aquitaine purebred young bulls from respectively 48, 36 and 30 sire families were genotyped with the Illumina Bovine SNP50 ® Beadchip. Two meat tenderness traits were measur ed: shear force and tenderness score. QTLs were detected with a methodology combining linkage disequilibrium and linkage analysis on haplotypes. If we consider the significant positions at the 1‰ threshold and separated by a minimum distance of 4cM, we found about 20 QTLs per trait in each of the three breeds, with a maximum of 35 QTL for shear force in the Blonde d’Aquitaine breed. Some QTL were common across two or three breeds as a QTL of shear force on the chromosome 3 between 16 and 21cM. Most of the other QTLs were breed-specific. The results were also consistent with previous studies of candidate genes (calpastatin and calpain 1 genes).