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.

Institute of Vertebrate Biology Academy of Sciences of the Czech Republic Brno Czech Republic

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Klein J (1986) Natural history of the major histocompatibility complex. New York: John Wiley and Sons. 775 p.

Janeway CA, Travers P, Walport M, Schlomchik MJ (2004) Immunobiology. New York: Garland Science. 800 p.

Bernatchez L, Landry C (2003) MHC studies in nonmodel vertebrates: what have we learned about natural selection in 15 years? J Evol Biol 16: 363–377. PubMed

Piertney SB, Oliver MK (2006) The evolutionary ecology of the major histocompatibility complex. Heredity 96: 7–21 doi:10.1038/sj.hdy.6800724 PubMed DOI

Schwensow N, Fietz J, Dausmann K, Sommer S (2008) MHC-associated mating strategies and the importance of overall genetic diversity in an obligate pair-living primate. Evol Ecol 22: 617–636 doi:10.1007/s10682-007-9186-4 DOI

Schwensow N, Eberle M, Sommer S (2008) Compatibility counts: MHC-associated mate choice in a wild promiscuous primate. Proc R Soc Lond B Biol Sci 275: 555–564 doi:10.1098/rspb.2007.1433 PubMed DOI PMC

Setchell JM, Vaglio S, Abbott KM, Moggi-Cecchi J, Boscaro F, et al. (2010) Odour signals major histocompatibility complex genotype in an Old World monkey. Proc R Soc Lond B Biol Sci 278: 274–280 doi:10.1098/rspb.2010.0571 PubMed DOI PMC

Eizaguirre C, Yeates SE, Lenz TL, Kalbe M, Milinski M (2009) MHC-based mate choice combines good genes and maintenance of MHC polymorphism. Mol Ecol 18: 3316–3329 doi:×10.1111/j.1365-294×.2009.04243.x PubMed DOI

Agbali M, Reichard M, Bryjova A, Bryja J, Smith C (2010) Mate choice for nonadditive genetic benefits correlate with MHC dissimilarity in the rose bitterling (Rhodeus ocellatus). Evolution 64: 1683–1696 doi:10.1111/j.1558-5646.2010.00961.x PubMed DOI

Bos DH, Williams RN, Gopurenko D, Bulut Z, Dewoody JA (2009) Condition dependent mate choice and a reproductive disadvantage for MHC-divergent male tiger salamanders. Mol Ecol 18: 3307–3315 doi:–10.1111/j.1365–294X.2009.04242.x PubMed DOI

Olsson M, Madsen T, Nordby J, Wapstra E, Ujvari B, et al. (2003) Major histocompatibility complex and mate choice in sand lizards. Proc R Soc Lond B Biol Sci 270: S254–S256 doi:10.1098/rsbl.2003.0079 PubMed DOI PMC

Miller HC, Moore JA, Nelson NJ, Daugherty CH (2009) Influence of major histocompatibility complex genotype on mating success in a free-ranging reptile population. Proc R Soc Lond B Biol Sci 276: 1695–1704 doi:10.1098/rspb.2008.1840 PubMed DOI PMC

von Schantz T, Wittzell H, Göransson G, Grahn M (1997) Mate choice, male condition dependent ornamentation and MHC in the pheasant. Hereditas 127: 133–140.

Freeman-Gallant CR, Meguerdichian M, Wheelwright NT, Sollecito SV (2003) Social pairing and female mating fidelity predicted by restriction fragment length polymorphism similarity at the major histocompatibility complex in a songbird. Mol Ecol 12: 3077–3083 doi:10.1046/j.1365-294X.2003.01968.x PubMed DOI

Ekblom R, Sæther A, Grahn M, Fiske P, Kålås JA, et al. (2004) Major histocompatibility complex variation and mate choice in a lekking bird, the great snipe (Gallinago media). Mol Ecol 13: 3821–3828 doi:10.1111/j.1365-294X.2004.02361.x PubMed DOI

Richardson DS, Komdeur J, Burke T, von Schantz T (2005) MHC-based patterns of social and extra-pair mate choice in the Seychelles warbler. Proc R Soc Lond B Biol Sci 272: 759–767 doi:10.1098/rspb.2004.3028 PubMed DOI PMC

Bonneaud C, Chastel O, Federici P, Westerdahl H, Sorci G (2006) Complex Mhc-based mate choice in a wild passerine. Proc R Soc Lond B Biol Sci 273: 1111–1116 doi:10.1098/rspb.2005.3325 PubMed DOI PMC

Brouwer L, Barr I, van de Pol M, Burke T, Komdeur J, et al. (2010) MHC-dependent survival in a wild population: evidence for hidden genetic benefits gained through extra-pair fertilizations. Mol Ecol 19: 3444–3455 doi:10.1111/j.1365-294X.2010.04750.x PubMed DOI

Griggio M, Biard C, Penn DJ, Hoi H (2011) Female house sparrows “count on” male genes: experimental evidence for MHC-dependent mate preference in birds. BMC Evol Biol 11: 44 doi:10.1186/1471-2148-11-44 PubMed DOI PMC

Promerová M, Vinkler M, Bryja J, Poláková R, Schnitzer J, et al. (2011) Occurrence of extra-pair paternity is connected to social male’s MHC-variability in the scarlet rosefinch Carpodacus erythrinus . J Avian Biol 42: 5–10 doi:10.1111/j.1600-048X.2010.05221.x DOI

von Schantz T, Wittzell H, Goransson G, Grahn M, Persson K (1996) MHC genotype and male ornamentation: genetic evidence for the Hamilton-Zuk model. Proc Biol Sci 263: 265–271. PubMed

Cutrera AP, Fanjul MS, Zenuto RR (2012) Females prefer good genes: MHC-associated mate choice in wild and captive tuco-tucos. Anim Behav 83: 847–856 doi:10.1016/j.anbehav.2012.01.006 DOI

Penn DJ, Potts WK (1999) The evolution of mating preferences and major histocompatibility complex genes. Am Nat 153: 145–164. PubMed

Briles WE, Goto RM, Auffray C, Miller MM (1993) A polymorphic system related to but genetically independent of the chicken major histocompatibility complex. Immunogenetics 37: 408–414 doi:10.1007/BF00222464 PubMed DOI

Miller MM, Goto RM, Taylor RL Jr, Zoorob R, Auffray C, et al. (1996) Assignment of Rfp-Y to the chicken major histocompatibility complex/NOR microchromosome and evidence for high-frequency recombination associated with the nucleolar organizer region. Proc Natl Acad Sci USA 93: 3958–3962. PubMed PMC

Miller MM, Bacon LD, Hala K, Hunt HD, Ewald SJ, et al. (2004) 2004 Nomenclature for the chicken major histocompatibility (B and Y) complex. Immunogenetics 56: 261–279 doi:10.1007/s00251-004-0682-1 PubMed DOI

Zoorob R, Behar G, Kroemer G, Auffray C (1990) Organization of a functional chicken class-II B-gene. Immunogenetics 31: 179–187. PubMed

Zoorob R, Bernot A, Renoir DM, Choukri F, Auffray C (1993) Chicken major histocompatibility complex class-II B-genes – analysis of interallelic and interlocus sequence variance. Eur J Immunol 23: 1139–1145 doi:10.1002/eji.1830230524 PubMed DOI

Hunt HD, Fulton JE (1998) Analysis of polymorphisms in the major expressed class I locus (B-FIV) of the chicken. Immunogenetics 47: 456–467. PubMed

Rogers S, Shaw I, Ross N, Nair V, Rothwell L, et al. (2003) Analysis of part of the chicken Rfp-Y region reveals two novel lectin genes, the first complete genomic sequence of a class I α-chain gene, a truncated class II β-chain gene, and a large CR1 repeat. Immunogenetics 55: 100–108 doi:10.1007/s00251-003-0553-1 PubMed DOI

Hunt HD, Goto RM, Foster DN, Bacon LD, Miller MM (2006) At least one YMHCI molecule in the chicken is alloimmunogenic and dynamically expressed on spleen cells during development. Immunogenetics 58: 297–307 doi:10.1007/s00251-005-0074-1 PubMed DOI

Strand T, Westerdahl H, Höglund J, Alatalo RV, Siitari H (2007) The Mhc class II of the Black grouse (Tetrao tetrix) consists of low numbers of B and Y genes with variable diversity and expression. Immunogenetics 59: 725–734 doi:10.1007/s00251-007-0234-6 PubMed DOI

Kaufman J, Völk H, Wallny HJ (1995) A ‘minimal essential Mhc’ and an ‘unrecognized Mhc’: two extremes in selection for polymorphism. Immunol Rev 143: 63–88. PubMed

Kaufman J, Milne S, Göbel TWF, Walker BA, Jacob JP, et al. (1999) The chicken B locus is a minimal essential major histocompatibility complex. Nature 401: 923–925 doi:10.1038/44856 PubMed DOI

Shaw I, Powell TJ, Marston DA, Baker K, van Hateren A, et al. (2007) Different evolutionary histories of the two classical class I genes BF1 and BF2 illustrate drift and selection within the stable MHC haplotypes of chickens. J Immunol 178: 5744–5752. PubMed

Hess CM, Edwards SV (2002) The evolution of major histocompatibility genes in birds. Bioscience 52: 423–431 doi:[];10.1641/0006-3568(2002)052[0423:TEOTMH]2.0.CO;2 DOI

Wittzell H, Bernot A, Auffray C, Zoorob R (1999) Concerted evolution of two Mhc class II B loci in pheasants and domestic chicken. Mol Biol Evol 16: 479–490. PubMed

Chaves LD, Faile GM, Krueth SB, Hendrickson JA, Reed KM (2010) Haplotype variation, recombination, and gene conversion within the turkey MHC-B locus. Immunogenetics 62: 465–477 doi:10.1007/s00251-010-0451-2 PubMed DOI

Shiina T, Shimizu S, Hosomichi K, Kohara S, Watanabe S, et al. (2004) Comparative genomic analysis of two avian (Quail and Chicken) MHC regions. J Immunol 172: 6751–6763. PubMed

Shiina T, Hosomichi K, Hanzawa K (2006) Comparative genomics of the poultry major histocompatibility complex. Anim Sci J 77: 151–162 doi:10.1111/j.1740-0929.2006.00333.x DOI

Hosomichi K, Shiina T, Suzuki S, Tanaka M, Shimizu S, et al. (2006) The major histocompatibility complex (Mhc) class IIB region has greater genomic structural flexibility and diversity in the quail than the chicken. BMC Genomics 7: 322–335 doi:10.1186/1471-2164-7-322 PubMed DOI PMC

Burri R, Niculita-Hirzel H, Roulin A, Fumagalli L (2008) Isolation and characterization of major histocompatibility complex (MHC) class II B genes in the Barn owl (Aves: Tyto alba). Immunogenetics 60: 543–550 doi:10.1007/s00251-008-0308-0 PubMed DOI

Burri R, Salamin N, Studer RA, Roulin A, Fumagalli L (2010) Adaptive divergence of ancient gene duplicates in the avian MHC class II β. Mol Biol Evol 27: 2360–2374 doi:10.1093/molbev/msq120 PubMed DOI

Ekblom R, Grahn M, Höglund J (2003) Patterns of polymorphism in the MHC class II of a non-passerine bird, the great snipe (Gallinago media). Immunogenetics 54: 734–741 doi:10.1007/s00251-002-0503-3 PubMed DOI

Westerdahl H, Wittzell H, von Schantz T (1999) Polymorphism and transcription of MHC class I genes in a passerine bird, the great reed warbler. Immunogenetics 49: 158–170 doi:10.1007/s002510050477 PubMed DOI

Westerdahl H, Wittzell H, von Schantz T (2000) MHC diversity in two passerine birds: no evidence for a minimal essential MHC. Immunogenetics 52: 92–100 doi:10.1007/s002510000256 PubMed DOI

Hess CM, Gasper J, Hoekstra H, Hill C, Edwards SV (2000) MHC class II pseudogene and genomic signature of a 32-kb cosmid in the House Finch (Carpodacus mexicanus). Genome Res 10: 13–23 doi:10.1101/gr.10.5.613 PubMed DOI PMC

Promerová M, Albrecht T, Bryja J (2009) Extremely high MHC class I variation in a population of a long-distance migrant, the Scarlet Rosefinch (Carpodacus erythrinus). Immunogenetics 61: 451–461 doi:10.1007/s00251-009-0375-x PubMed DOI

Anmarkrud JA, Johnsen A, Bachmann L, Lifjeld JT (2010) Ancestral polymorphism in exon 2 of bluethroat (Luscinia svecica) MHC class II B genes. J Evol Biol 23: 1206–1217 doi:10.1111/j.1420-9101.2010.01999.x PubMed DOI

Sepil I, Moghadam HK, Huchard E, Sheldon BC (2012) Characterization and 454 pyrosequencing of Major Histocompatibility Complex class I genes in the great tit reveal complexity in a passerine system. BMC Evol Biol 12: 68 doi:10.1186/1471-2148-12-68 PubMed DOI PMC

Zagalska-Neubauer M, Babik W, Stuglik M, Gustafsson L, Cichon M, et al. (2010) 454 sequencing reveals extreme complexity of the class II major histocompatibility complex in the collared flycatcher. BMC Evol Biol 10: 395 doi:10.1186/1471-2148-10-395 PubMed DOI PMC

Hedges SB, Dudley J, Kumar S (2006) TimeTree: a public knowledge-base of divergence times among organisms. Bioinformatics 22: 2971–2972 doi:10.1093/bioinformatics/btl505 PubMed DOI

Leo GA, Focardi S, Gatto M, Cattadori IM (2004) The decline of the Grey Partridge in Europe: comparing demographies in traditional and modern agricultural landscapes. Ecol Model 177: 313–335 doi:10.1016/j.ecolmodel.2003.11.017 DOI

EBCC (2012) Pan-European Common Bird Monitoring Scheme. Available: http://www.ebcc.info/index.php?ID=457. Accessed 2012 Feb 28.

Radwan J, Biedrzycka A, Babik W (2010) Does reduced MHC diversity decrease viability of vertebrate populations? Biol Conserv 143: 537–544 doi:10.1016/j.biocon.2009.07.026 PubMed DOI PMC

Říčanová Š, Bryja J, Cosson J-F, Gedeon C, Choleva L, et al. (2011) Depleted genetic variation of the European ground squirrel in Central Europe in both microsatellites and the major histocompatibility complex gene: implications for conservation. Conserv Genet 12: 1115–1129 doi:10.1007/s10592-011-0213-1 DOI

Beani L, Dessì-Fulgheri F (1995) Mate choice in the grey partridge, Perdix perdix: role of physical and behavioural male traits. Anim Behav 49: 347–356 doi:10.1006/anbe.1995.0047 DOI

Hall TA (1999) BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symp Ser 41: 95–98.

Thompson JD, Higgins DG, Gibson TJ (1994) Clustal-W: Improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. Nucl Acid Res 22: 4673–4680 doi:10.1093/nar/22.22.4673 PubMed DOI PMC

Kosakovsky Pond SL, Posada D, Gravenor MB, Woelk CH, Frost SDW (2006) Automated phylogenetic detection of recombination using a genetic algorithm. Mol Biol Evol 23: 1891–1901 doi:10.1093/molbev/msl051 PubMed DOI

Yang Z (2007) PAML 4: phylogenetic analysis by maximum likelihood. Mol Biol Evol 24: 1586–1591. PubMed

Yang Z, Swanson WJ, Vacquier VD (2000) Maximum-likelihood analysis of molecular adaptation in abalone sperm lysin reveals variable selective pressures among lineages and sites. Mol Biol Evol 17: 1446–1455. PubMed

Yang Z, Wong WSW, Nielsen R (2005) Bayes empirical Bayes inference of amino acid sites under positive selection. Mol Biol Evol 22: 1107–1118 doi:10.1093/molbev/msi097 PubMed DOI

Brown JH, Jardetzky TS, Gorga JC, Stern LJ, Urban RG, et al. (1993) Three-dimensional structure of the human class II histocompatibility antigen HLA-DR1. Nature 364: 33–39 doi:10.1038/364033a0 PubMed DOI

Tamura K, Peterson D, Peterson N, Stecher G, Nei M, et al. (2011) MEGA5: Molecular Evolutionary Genetics Analysis Using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods. Mol Biol Evol 28: 2731–2739 doi:10.1093/molbev/msr121 PubMed DOI PMC

Sawyer SA (1999) GENECONV: a computer package for the statistical detection of gene conversion. Distributed by the author, Department of Mathematics, Washington University in St. Louis. Available: http://www.math.wustl.edu/~sawyer/geneconv/

Guindon S, Dufayard JF, Lefort V, Anisimova M, Hordijk W, et al. (2010) New algorithms and methods to estimate maximum-likelihood phylogenies: assessing the performance of PhyML 3.0. Syst Biol 59: 307–321. PubMed

Klein J, Bontrop RE, Dawkins RL, Erlich HA, Gyllensten UB, et al. (1990) Nomenclature for the major histocompatibility complexes of different species: a proposal. Immunogenetics 31: 217–219. PubMed

Worley K, Gillingham M, Jensen P, Kennedy LJ, Pizzari T, et al. (2008) Single locus typing of MHC class I and class II B loci in a population of red jungle fowl. Immunogenetics 60: 233–247 doi:10.1007/s00251-008-0288-0 PubMed DOI

Ekblom R, Sæther SA, Jacobsson P, Fiske P, Sahlman T, et al. (2007) Spatial pattern of MHC class II variation in the great snipe (Gallinago media). Mol Ecol 16: 1439–1451. PubMed

Alcaide M, Edwards SV, Negro JJ, Serrano D, Tella JL (2008) Extensive polymorphism and geographical variation at a positively selected MHC class II B gene of the lesser kestrel (Falco naumanni). Mol Ecol 17: 2652–2665 doi:10.1111/j.1365-294X.2008.03791.x PubMed DOI

Chaves LD, Krueth SB, Reed KM (2009) Defining the turkey MHC: sequence and genes of the B locus. J Immunol 183: 6530–6537 doi:10.4049/jimmunol.0901310 PubMed DOI

Eimes JA, Bollmer JL, Dunn PO, Whittingham LA, Wimpee C (2010) Mhc class II diversity and balancing selection in greater prairie-chickens. Genetica 138: 265–271 doi:10.1007/s10709-009-9417-4 PubMed DOI

Bryja J, Galan M, Charbonnel N, Cosson J-F (2005) Analysis of major histocompatibility complex class II gene in water voles using capillary electrophoresis-single stranded conformation polymorphism. Mol Ecol Notes 5: 173–176 doi:10.1111/j.1471-8286.2004.00855.x DOI

Babik W (2010) Methods for MHC genotyping in non-model vertebrates. Mol Ecol Resour 10: 237–251 doi:10.1111/j.1755-0998.2009.02788.x PubMed DOI

Promerová M, Babik W, Bryja J, Albrecht T, Stuglik M, et al. (2012) Evaluation of two approaches to genotyping major histocompatibility complex class I in a passerine – CE-SSCP and 454 pyrosequencing. Mol Ecol Resour 12: 285–292 doi:10.1111/j.1755-0998.2011.03082.x PubMed DOI

Goüy de Bellocq J, Suchentrunk F, Baird SJE, Schaschl H (2009) Evolutionary history of an MHC gene in two leporid species: characterisation of MHC-DQA in the European brown hare and comparison with the European rabbit. Immunogenetics 61: 131–144 doi:10.1007/s00251-008-0349-4 PubMed DOI

Čížková D, Goüy de Bellocq J, Baird SJE, Piálek J, Bryja J (2011) Genetic structure and contrasting selection pattern at two major histocompatibility complex genes in wild house mouse populations. Heredity 106: 727–740 doi:10.1038/hdy.2010.112 PubMed DOI PMC

Baratti M, Ammannati M, Magnelli C, Massolo A, Dessì-Fulgheri F (2010) Are large wattles related to particular MHC genotypes in the male pheasant? Genetica 138: 657–665 doi:10.1007/s10709-010-9440-5 PubMed DOI

Radwan J, Zagalska-Neubauer M, Cichon M, Sendecka J, Kulma K, et al. (2012) MHC diversity, malaria and lifetime reproductive success in collared flycatchers. Mol Ecol 21: 2469–2479 doi:10.1111/j.1365-294X.2012.05547.x PubMed DOI

Wittzell H, von Schantz T, Zoorob R, Auffray C (1995) Rfp-Y-like sequences assort independently of pheasant Mhc genes. Immunogenetics 42: 68–71. PubMed

Reed KM, Bauer MM, Monson MS, Benoit B, Chaves LD, et al. (2011) Defining the turkey MHC: identification of expressed class I- and IIB-like genes independent of the MHC-B. Immunogenetics 63: 753–771 doi:10.1007/s00251-011-0549-1 PubMed DOI

Afanassieff M, Goto RM, Ha J, Sherman MA, Zhong L, et al. (2001) At least one class I gene in restriction fragment pattern-Y (Rfp-Y), the second MHC gene cluster in the chicken, is transcribed, polymorphic, and shows divergent specialization in antigen binding region. J Immunol 166: 3324–3333. PubMed

Star B, Nederbragt AJ, Jentoft S, Grimholt U, Malmstrøm M, et al. (2011) The genome sequence of Atlantic cod reveals a unique immune system. Nature 477: 207–210 doi:10.1038/nature10342 PubMed DOI PMC

Strandh M, Lannefors M, Bonadonna F, Westerdahl H (2011) Characterization of MHC class I and II genes in a subantarctic seabird, the blue petrel, Halobaena caerulea (Procellariiformes). Immunogenetics 63: 653–666 doi:10.1007/s00251-011-0534-8 PubMed DOI

Borg AA, Pedersen SA, Jensen H, Westerdahl H (2011) Variation in MHC genotypes in two populations of house sparrow (Passer domesticus) with different population histories. Ecol Evol 1: 145–159 doi:10.1002/ece3.13 PubMed DOI PMC

Ohta T (1991) Role of diversifying selection and gene conversion in evolution of major histocompatibility complex loci. Proc Natl Acad Sci USA 88: 6716–6720. PubMed PMC

Ohta T (1995) Gene conversion vs point mutation in generating variability at the antigen recognition site of major histocompatibility complex loci. J Mol Evol 41: 115–119. PubMed

Spurgin LG, van Oosterhout C, Illera JC, Bridgett S, Gharbi K, et al. (2011) Gene conversion rapidly generates major histocompatibility complex diversity in recently founded bird populations. Mol Ecol 20: 5213–5225 doi:–10.1111/j.1365–294X.2011.05367.x PubMed DOI

Miller HC, Bowker-Wright G, Kharkrang M, Ramstad K (2011) Characterisation of class II B MHC genes from a ratite bird, the little spotted kiwi (Apteryx owenii). Immunogenetics 63: 223–233 doi:10.1007/s00251-010-0503-7 PubMed DOI

Eo SH, Bininda-Emonds ORP, Carroll JP (2009) A phylogenetic supertree of the fowls (Galloanserae, Aves). Zool Scr 38: 465–481 doi:10.1111/j.1463-6409.2008.00382.x DOI

Shen Y, Liang L, Sun Y, Yue B, Yang X, et al. (2010) A mitogenomic perspective on the ancient, rapid radiation in the Galliformes with an emphasis on the Phasianidae. BMC Evol Biol 10: 132. PubMed PMC

Nei M, Gojobori T (1986) Simple methods for estimating the numbers of synonymous and nonsynonymous nucleotide substitutions. Mol Biol Evol 3: 418–426. PubMed

Lambourne MD, Si W, Niemiec PK, Read LR, Kariyawasam S, et al. (2005) Identification of novel polymorphisms in the B-LB locus of Gallus lafayettei. Anim Genet 36: 435–462 doi: 10.1111/j.1365-2052.2005.01332.x PubMed DOI

Singh SK, Mehra S, Kumar V, Shukla SK, Tiwari A, et al. (2010) Sequence variability in the BLB2 region among guinea fowl and other poultry species. Int J Genet Mol Biol 2: 048–051.

Hale ML, Verduijn MH, Moller AP, Wolff K, Petrie M (2009) Is the peacock’s train an honest signal of genetic quality at the major histocompatibility complex? J Evol Biol 22: 1284–1294 doi:10.1111/j.1420-9101.2009.01746.x PubMed DOI

Mate choice for major histocompatibility complex complementarity in a strictly monogamous bird, the grey partridge (Perdix perdix)