title: Characterization of MHC-I in the blue tit (Cyanistes caeruleus) reveals low levels of genetic diversity and trans-population evolution across European populations.
abstract: The major histcompatibility complex (MHC) is a vital component of the adaptive immune system in all vertebrates. This study is the first to characterize MHC class I (MHC-I) in blue tits (Cyanistes caeruleus), and we use MHC-I exon 3 sequence data from individuals originating from three locations across Europe: Spain, the Netherlands to Sweden. Our phylogeny of the 17 blue tit MHC-I alleles contains one allele cluster with low nucleotide diversity compared to the remaining more diverse alleles. We found a significant evidence for balancing selection in the peptide-binding region in the diverse allele group only. No separation according to geographic location was found in the phylogeny of alleles. Although the number of MHC-I loci of the blue tit is comparable to that of other passerine species, the nucleotide diversity of MHC-I appears to be much lower than that of other passerine species, including the closely related great tit (Parus major) and the severely inbred Seychelles warbler (Acrocephalus sechellensis). We believe that this initial MHC-I characterization in blue tits provides an important step towards understanding the mechanisms shaping MHC-I diversity in natural populations.
authors.affiliation: Animal Ecology Group/Behavioural Ecology and Self-Organisation, Centre for Ecological and Evolutionary Studies, University of Groningen, The Netherlands. elske.schut@rug.nl
authors.forename: Elske
authors.initials: E
authors.lastname: Schut
authors.forename: Juan Rivero-de
authors.initials: JR
authors.lastname: Aguilar
authors.forename: Santiago
authors.initials: S
authors.lastname: Merino
authors.forename: Michael J L
authors.initials: MJ
authors.lastname: Magrath
authors.forename: Jan
authors.initials: J
authors.lastname: Komdeur
authors.forename: Helena
authors.initials: H
authors.lastname: Westerdahl
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005060:Europe; D019143:Evolution, Molecular; D014644:Genetic Variation; D005828:Genetics, Population; D015395:Histocompatibility Antigens Class I / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D046109:Passeriformes / Q000235:genetics*; D010802:Phylogeny; D016415:Sequence Alignment
chemical_list: D015395:Histocompatibility Antigens Class I