Genome-wide association studies for resistance to viral nervous necrosis in three populations of European sea bass (Dicentrarchus labrax) using a novel 57k SNP array DlabChip

Viral Nervous Necrosis (VNN) is a major threat for the European sea bass (Dicentrarchus labrax) aquaculture industry. The improvement of disease resistance through selective breeding promising option to reduce outbreaks. With development high-throughput genotyping technologies, identification genomic regions involved in could improve efficiency breeding. aim this study was identify quantitative trait loci (QTL) VNN and quantify their effect. Four experimental backcross families comprising 378, 454, 291 211 individuals two commercial populations A B 1027 1042 obtained from partial factorial crosses (59♂ x 20♀ pop A; 39♂ 14♀ B) were submitted redspotted grouper nervous necrosis virus (RGNNV) challenge by bath. high-density single nucleotide polymorphism (SNP) chip panel designed develop ThermoFisher Axiom™ 57k SNP DlabChip, which used all building high quality linkage map. In families, composite interval mapping performed on 30,917, 23,592, 30,656 31,490 markers, respectively. populations, 40,263 markers 41,166 perform genome-wide association studies (GWAS) using GBLUP BayesCπ approach. One QTL identified chromosome LG12 three four one additional LG8 detected only family. revealed total seven QTLs, among previously mentioned both. This QTL, mapped an 3.45 cM, explained 9.21% genetic variance A, while other QTLs individually less than 1% variance. bass, with having strong effect, should have great impact Future work focus fine causal mutation present whole genome sequencing.