title: Evolution of the polymorphism at molecular markers in QTL and non-QTL regions in selected chicken lines (Open Access publication).
abstract: We investigated the joint evolution of neutral and selected genomic regions in three chicken lines selected for immune response and in one control line. We compared the evolution of polymorphism of 21 supposedly neutral microsatellite markers versus 30 microsatellite markers located in seven quantitative trait loci (QTL) regions. Divergence of lines was observed by factor analysis. Five supposedly neutral markers and 12 markers in theQTL regions showed F(st) values greater than 0.15. However, the non-significant difference (P > 0.05) between matrices of genetic distances based on genotypes at supposedly neutral markers on the one hand, and at markers in QTL regions, on the other hand, showed that none of the markers in the QTL regions were influenced by selection. A supposedly neutral marker and a marker located in the QTL region on chromosome 14 showed temporal variations in allele frequencies that could not be explained by drift only. Finally, to confirm that markers located inQTL regions on chromosomes 1, 7 and 14 were under the influence of selection, simulations were performed using haplotype dropping along the existing pedigree. In the zone located on chromosome 14, the simulation results confirmed that selection had an effect on the evolution of polymorphism of markers within the zone.
authors.affiliation: Génétique et Diversité Animales UMR1236, INRA/AgroParisTech, 78352 Jouy-en-Josas, France. valerie.loywyck@agroparistech.fr
authors.forename: Valérie
authors.initials: V
authors.lastname: Loywyck
authors.forename: Bertrand
authors.initials: B
authors.lastname: Bed'hom
authors.forename: Marie-Héle Ne
authors.initials: MH
authors.lastname: Pinard-van der Laan
authors.forename: Frédérique
authors.initials: F
authors.lastname: Pitel
authors.forename: Etienne
authors.initials: E
authors.lastname: Verrier
authors.forename: Piter
authors.initials: P
authors.lastname: Bijma
mesh_terms: D000818:Animals; D002645:Chickens / Q000235:genetics* / Q000276:immunology; D019143:Evolution, Molecular; D005163:Factor Analysis, Statistical; D005787:Gene Frequency; D040961:Genetic Drift; D018895:Microsatellite Repeats; D008957:Models, Genetic; D011110:Polymorphism, Genetic; D011156:Population Density; D040641:Quantitative Trait Loci; D012641:Selection, Genetic