Immunogenetics

, Volume 44, Issue 1, pp 1–8

Structure and organization of pigMHC class IIDRB genes: evidence for genetic exchange between loci

Authors

  • Ulrica Brunsberg
    • Department of Medical Inflammation ResearchLund University
  • Inger Edfors-Lilja
    • Department of Animal Breeding and GeneticsSwedish University of Agricultural Sciences, Uppsala Biomedical Center
  • Leif Andersson
    • Department of Animal Breeding and GeneticsSwedish University of Agricultural Sciences, Uppsala Biomedical Center
  • Kenth Gustafsson
    • Division of Cell and Molecular Biology, Institute of Child HealthUniversity of London
Original Paper

DOI: 10.1007/BF02602651

Cite this article as:
Brunsberg, U., Edfors-Lilja, I., Andersson, L. et al. Immunogenetics (1996) 44: 1. doi:10.1007/BF02602651

Abstract

The pig major histocompatibility complexDRB genes were studied by polymerase chain reaction (PCR) amplification of exon 2 from eight domestic pigs and two European wild boars. Sequence comparisons together with a phylogenetic analysis showed the existence of at least threeDRB genes of which only one appears to be expressed. The two putativeDRB pseudogenes contained delections in exon 2, making it possible to confirm the presence of three non-allelicDRB genes by analyzing the length polymorphism of the amplified PCR products. The expressed gene shows allelic polymorphism at the same positions as in the humanDRB1 gene. In addition this pig gene shows extensive allelic polymorphism at positions 84–88, whereas, e.g., humanDRB genes do not. Surprisingly, the the two putativeDRB pseudogenes also display a considerable amount of allelic polymorphism, albeit of a different character as compared with the expressedDRB gene. Short stretches of sequences are shared between individual alleles at different loci. These sequence similarities cannot be due to natural selection, since two of the threeDRB genes involved are polymorphic pseudogenes constituting allelic series that have diverged after the inactivation event. Instead, the results indicate that the sequences have been exchanged between theDRB genes by intergenic recombination.

Copyright information

© Springer-Verlag 1996