Among bird species, the most studied major histocompatibility complex (MHC) is the chicken MHC. Although the number of studies on MHC in free-ranging species is increasing, the knowledge on MHC variation in species closely related to chicken is required to understand the peculiarities of bird MHC evolution. Here we describe the variation of MHC class IIB (MHCIIB) exon 2 in a population of the Grey partridge (Perdix perdix), a species of high conservation concern throughout Europe and an emerging galliform model in studies of sexual selection. We found 12 alleles in 108 individuals, but in comparison to other birds surprisingly many sites show signatures of historical positive selection. Individuals displayed between two to four alleles both on genomic and complementary DNA, suggesting the presence of two functional MHCIIB loci. Recombination and gene conversion appear to be involved in generating MHCIIB diversity in the Grey partridge; two recombination breakpoints and several gene conversion events were detected. In phylogenetic analysis of galliform MHCIIB, the Grey partridge alleles do not cluster together, but are scattered through the tree instead. Thus, our results indicate that the Grey partridge MHCIIB is comparable to most other galliforms in terms of copy number and population polymorphism.

• MeSH
• alely MeSH
• druhová specificita MeSH
• exony genetika   MeSH
• fylogeneze MeSH
• Galliformes genetika   MeSH
• genová konverze * MeSH
• MHC antigeny II. třídy chemie   genetika   MeSH
• molekulární sekvence - údaje MeSH
• polymorfismus genetický * MeSH
• pravděpodobnostní funkce MeSH
• regulace genové exprese MeSH
• rekombinace genetická genetika   MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční seřazení MeSH
• selekce (genetika) * MeSH
• substituce aminokyselin genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• MHC antigeny II. třídy MeSH

The mammalian major histocompatibility complex (MHC) is a tightly linked cluster of immune genes, and is often thought of as inherited as a unit. This has led to the hope that studying a single MHC gene will reveal patterns of evolution representative of the MHC as a whole. In this study we analyse a 1000-km transect of MHC variation traversing the European house mouse hybrid zone to compare signals of selection and patterns of diversification at two closely linked MHC class II genes, H-2Aa and H-2Eb. We show that although they are 0.01 cM apart (that is, recombination is expected only once in 10 000 meioses), disparate evolutionary patterns were detected. H-2Aa shows higher allelic polymorphism, faster allelic turnover due to higher mutation rates, stronger positive selection at antigen-binding sites and higher population structuring than H-2Eb. H-2Eb alleles are maintained in the gene pool for longer, including over separation of the subspecies, some H-2Eb alleles are positively and others negatively selected and some of the alleles are not expressed. We conclude that studies on MHC genes in wild-living vertebrates can give substantially different results depending on the MHC gene examined and that the level of polymorphism in a related species is a poor criterion for gene choice.

• MeSH
• alely * MeSH
• DNA primery genetika   MeSH
• fylogeneze MeSH
• genetická variace * MeSH
• genetické komponenty MeSH
• hlavní histokompatibilní komplex genetika   MeSH
• hybridizace genetická * MeSH
• modely genetické MeSH
• molekulární evoluce * MeSH
• molekulární sekvence - údaje MeSH
• myši genetika   MeSH
• populační genetika MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sekvenční seřazení MeSH
• selekce (genetika) * MeSH
• shluková analýza MeSH
• zvířata MeSH
• Check Tag
• myši genetika   MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• DNA primery MeSH