Etude de la capacité immunitaire chez le porc Large White : recherche de marqueurs génétiques liés à l'expression des gènes dans le sang

Tatiana Maroilley et al., 48es Journée de la Recherche Porcine (FRA), 2-3 février 2016, Paris, p. 285-286, poster

Poster.

FR

En élevage porcin, les schémas de sélection cherchent à produire des animaux plus robustes afin, notamment, de réduire l’usage des antibiotiques. Nous avons engagé des recherches qui visent à qualifier la compétence immunitaire des animaux et étudions l'architecture génétique de paramètres immuns dans des populations d'animaux cliniquement sains. Nous avons déjà montré que de nombreux paramètres immunitaires sont héritables (Flori et al. 2011) et que le transcriptome du sang est informatif pour quantifier certains d'entre eux (Mach et al. 2013). Notre objectif est maintenant d'identifier des marqueurs génétiques associés à la variation d'expression des gènes dans le sang.

ENG

Analysis of the immune capacity in Large White pigs: search for genetic markers linked to the variation of gene expression in the blood

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 surrogate 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 the genetic architecture of immunity trait variations in pigs, and contribute to paving the way towards a qualification of the individual immune capacity for translational research in precision pig farming.