Etude de la capacité immunitaire chez le porc Large White : recherche de marqueurs génétiques liés à l'expression des gènes dans le sang
Résumé
Combining animal production performances and health traits is a main issue in livestock farming. Blood is emerging as a source of biological information linked to the health and physiological state of each individual. Furthermore, it is an interesting sur rogate tissue for animal phenotyping because its sampling is almost non-invasive and reproducible. We have already shown that several immune parameters are heritable and that the blood transcriptome is informative to quantify some of them. In this study, our aim was to identify genetic markers associated with gene expression variations in the blood, based on an expression genome-wide association study (eGWAS) using 243 Large White pigs at 60 days of age. Each pig was genotyped with the Illumina iSelect 60K Chip and the blood transcriptome analysis was performed by using a custom gene expression 8X60K microarray (Agilent Technologies). 4,591 significant associations between one SNP and one probe were found, including 62% cis-associations (the associated SNP is in a window of 2Mb surrounding the probe). Among the 3,419 probes with at least one associated SNP (eQTL), 70% had a cis-eQTL and 89% could be assigned to a porcine gene. The eQTLs were found to be linked with the expression of one to 51 genes. The genomic regions surrounding the eQTLs correspond to candidate regions to further study thegenetic architecture of immunity trait variations in pigs, and contribute to paving the way towards a qualification of the individual immune capacity for tran slational research in precision pig farming.