title: On estimation and identifiability issues of sex-linked inheritance with a case study of pigmentation in Swiss barn owl (Tyto alba).
abstract: Genetic evaluation using animal models or pedigree-based models generally assume only autosomal inheritance. Bayesian animal models provide a flexible framework for genetic evaluation, and we show how the model readily can accommodate situations where the trait of interest is influenced by both autosomal and sex-linked inheritance. This allows for simultaneous calculation of autosomal and sex-chromosomal additive genetic effects. Inferences were performed using integrated nested Laplace approximations (INLA), a nonsampling-based Bayesian inference methodology. We provide a detailed description of how to calculate the inverse of the X- or Z-chromosomal additive genetic relationship matrix, needed for inference. The case study of eumelanic spot diameter in a Swiss barn owl (Tyto alba) population shows that this trait is substantially influenced by variation in genes on the Z-chromosome ([Formula: see text] and [Formula: see text]). Further, a simulation study for this study system shows that the animal model accounting for both autosomal and sex-chromosome-linked inheritance is identifiable, that is, the two effects can be distinguished, and provides accurate inference on the variance components.
authors: Department of Mathematical Sciences, NTNU NO-7491, Trondheim, Norway.
authors: Camilla T
authors: CT
authors: Larsen
authors: Department of Mathematical Sciences, Centre for Biodiversity Dynamics, NTNU NO-7491, Trondheim, Norway.
authors: Anna M
authors: AM
authors: Holand
authors: Department of Biology, Centre for Biodiversity Dynamics, NTNU NO-7491, Trondheim, Norway.
authors: Henrik
authors: H
authors: Jensen
authors: Department of Mathematical Sciences, Centre for Biodiversity Dynamics, NTNU NO-7491, Trondheim, Norway.
authors: Ingelin
authors: I
authors: Steinsland
authors: Department of Ecology and Evolution, University of Lausanne 1015, Lausanne, Switzerland.
authors: Alexandre
authors: A
authors: Roulin
keywords: Approximate Bayesian animal model; barn owl (Tyto alba); integrated nested Laplace approximation; quantitative genetics; sex chromosome; sex-linked additive genetic effects