Résumé
The recent progress and cost reduction of genotyping technologies allows for the implementation of genomic selection (GS) on more and more cultivated species. In this study, we explore the genomic determinism of commercial traits and test the effectiveness and the possible cost reduction of GS in breeding programs of the cupped oyster Crassostrea gigas. Two populations of more than 1000 individuals have been phenotyped and genotyped for 40,000 SNP (Guitierez et al., 2017). Heritability was estimated to be moderate for commercial traits of interest (between 0.19 and 0.34). The accuracy of the genomic prediction models outperformed the classical selection on pedigree by 22 to 55%. A limited linkage disequilibrium (LD) level (less than 0.1) was observed. These results suggest that the use of GS in oyster breeding can improve the selection of breeding candidates to enhance commercial traits but need a specific account and exploration of the very low LD.