Abstracts (first author)
Quantitative trait genes for fearful behaviour under chicken domesticationPDF
Domestication is a form of strong directional selection imparting wide-ranging phenotypic changes to animals and plants, and ever since Darwin considered a model of evolution. Changes in behaviour, particularly fearful and social behaviour, are at the heart of animal domestication. A wild by domestic advanced intercross of chickens is a powerful study system for the genetics and genomics of domestication phenotypes. We applied quantitative trait locus (QTL) mapping and genetical genomics to fear-related behaviours.
QTL mapping in 572 birds from an eight-generation intercross revealed ~44 loci for behaviour in three test situations: an open field, a social reinstatement, and a tonic immobility test. The tests have separate but overlapping architectures with a few potentially pleiotropic loci and small to moderate QTL effect sizes.
To search for underlying genes we mapped transcriptome-wide expression QTL (eQTL) in hypothalamus from 129 birds. Out of 634 eQTL, 16 candidate quantitative trait genes had eQTL coinciding with behaviour QTL and a gene expression—behaviour correlation.
Structural equations modelling found eight genes in four QTL to be consistent with a causal role of gene expression: PRDX4 (a periredoxin), ACOT9 (an acyl-coenzyme A thioesterase) and SRPX (Sushi repeat-containing) are candidates for a social reinstatement and tonic immobility locus on chromosome 1; TTRAP (TRAF and TNF receptor-associated protein) and an unknown EST sequence 60386624F1 for a social reinstatement QTL on chromosome 2; ADAM10 (disintegrin and metalloproteinase domain-containing) and APBA2 (Amyloid beta A4 precursor protein-binding) for an open field locus on chromosome 10; and the unknown LOC770352 for a second open field QTL on chromsome 10.
In conclusion, our mapping gives genetic and gene expression evidence for unexpected putative quantitative trait genes for fearful behaviour under chicken domestication.