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Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology

The domestication of animals has generated a set of phenotypic modifications, affecting behaviour, appearance, physiology and reproduction, which are consistent across a range of species. We hypothesized that some of these phenotypes could have evolved because of genetic correlation to tameness, an...

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Autores principales: Bélteky, Johan, Agnvall, Beatrix, Johnsson, Martin, Wright, Dominic, Jensen, Per
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5108935/
https://www.ncbi.nlm.nih.gov/pubmed/27853585
http://dx.doi.org/10.1098/rsos.160033
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author Bélteky, Johan
Agnvall, Beatrix
Johnsson, Martin
Wright, Dominic
Jensen, Per
author_facet Bélteky, Johan
Agnvall, Beatrix
Johnsson, Martin
Wright, Dominic
Jensen, Per
author_sort Bélteky, Johan
collection PubMed
description The domestication of animals has generated a set of phenotypic modifications, affecting behaviour, appearance, physiology and reproduction, which are consistent across a range of species. We hypothesized that some of these phenotypes could have evolved because of genetic correlation to tameness, an essential trait for successful domestication. Starting from an outbred population of red junglefowl, ancestor of all domestic chickens, we selected birds for either high or low fear of humans for five generations. Birds from the fifth selected generation (S(5)) showed a divergent pattern of growth and reproduction, where low fear chickens grew larger and produced larger offspring. To examine underlying genetic mechanisms, we used microarrays to study gene expression in thalamus/hypothalamus, a brain region involved in fear and stress, in both the parental generation and the S(5). While parents of the selection lines did not show any differentially expressed genes, there were a total of 33 genes with adjusted p-values below 0.1 in S(5). These were mainly related to sperm-function, immunological functions, with only a few known to be relevant to behaviour. Hence, five generations of divergent selection for fear of humans produced changes in hypothalamic gene expression profiles related to pathways associated with male reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis that domesticated phenotypes may evolve because of correlated effects related to reduced fear of humans.
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spelling pubmed-51089352016-11-16 Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology Bélteky, Johan Agnvall, Beatrix Johnsson, Martin Wright, Dominic Jensen, Per R Soc Open Sci Biology (Whole Organism) The domestication of animals has generated a set of phenotypic modifications, affecting behaviour, appearance, physiology and reproduction, which are consistent across a range of species. We hypothesized that some of these phenotypes could have evolved because of genetic correlation to tameness, an essential trait for successful domestication. Starting from an outbred population of red junglefowl, ancestor of all domestic chickens, we selected birds for either high or low fear of humans for five generations. Birds from the fifth selected generation (S(5)) showed a divergent pattern of growth and reproduction, where low fear chickens grew larger and produced larger offspring. To examine underlying genetic mechanisms, we used microarrays to study gene expression in thalamus/hypothalamus, a brain region involved in fear and stress, in both the parental generation and the S(5). While parents of the selection lines did not show any differentially expressed genes, there were a total of 33 genes with adjusted p-values below 0.1 in S(5). These were mainly related to sperm-function, immunological functions, with only a few known to be relevant to behaviour. Hence, five generations of divergent selection for fear of humans produced changes in hypothalamic gene expression profiles related to pathways associated with male reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis that domesticated phenotypes may evolve because of correlated effects related to reduced fear of humans. The Royal Society 2016-08-03 /pmc/articles/PMC5108935/ /pubmed/27853585 http://dx.doi.org/10.1098/rsos.160033 Text en © 2016 The Authors. http://creativecommons.org/licenses/by/4.0/ Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.
spellingShingle Biology (Whole Organism)
Bélteky, Johan
Agnvall, Beatrix
Johnsson, Martin
Wright, Dominic
Jensen, Per
Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
title Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
title_full Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
title_fullStr Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
title_full_unstemmed Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
title_short Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
title_sort domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
topic Biology (Whole Organism)
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5108935/
https://www.ncbi.nlm.nih.gov/pubmed/27853585
http://dx.doi.org/10.1098/rsos.160033
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