Immunogenetics

, Volume 61, Issue 4, pp 303–314

Contrasting evolution of diversity at two disease-associated chicken genes

  • Tim Downing
  • David J. Lynn
  • Sarah Connell
  • Andrew T. Lloyd
  • AK Fazlul Haque Bhuiyan
  • Pradeepa Silva
  • Arifa N. Naqvi
  • Rahamame Sanfo
  • Racine-Samba Sow
  • Baitsi Podisi
  • Cliona O’Farrelly
  • Olivier Hanotte
  • Daniel G. Bradley
Original Paper

DOI: 10.1007/s00251-009-0359-x

Cite this article as:
Downing, T., Lynn, D.J., Connell, S. et al. Immunogenetics (2009) 61: 303. doi:10.1007/s00251-009-0359-x

Abstract

There have been significant evolutionary pressures on the chicken during both its speciation and its subsequent domestication by man. Infectious diseases are expected to have exerted strong selective pressures during these processes. Consequently, it is likely that genes associated with disease susceptibility or resistance have been subject to some form of selection. Two genes involved in the immune response (interferon-γ and interleukin 1-β) were selected for sequencing in diverse chicken populations from Pakistan, Sri Lanka, Bangladesh, Kenya, Senegal, Burkina Faso and Botswana, as well as six outgroup samples (grey, green, red and Ceylon jungle fowl and grey francolin and bamboo partridge). Haplotype frequencies, tests of neutrality, summary statistics, coalescent simulations and phylogenetic analysis by maximum likelihood were used to determine the population genetic characteristics of the genes. Networks indicate that these chicken genes are most closely related to the red jungle fowl. Interferon-γ had lower diversity and considerable coding sequence conservation, which is consistent with its function as a key inflammatory cytokine of the immune response. In contrast, the pleiotropic cytokine interleukin 1-β had higher diversity and showed signals of balancing selection moderated by recombination, yielding high numbers of diverse alleles, possibly reflecting broader functionality and potential roles in more diseases in different environments.

Keywords

Chicken Interleukin 1 beta Interferon gamma Selection Population genetics 

Supplementary material

251_2009_359_MOESM1_ESM.doc (3.4 mb)
Supplementary material 1(DOC 3.40 MB)

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Tim Downing
    • 1
  • David J. Lynn
    • 2
  • Sarah Connell
    • 1
  • Andrew T. Lloyd
    • 3
  • AK Fazlul Haque Bhuiyan
    • 4
  • Pradeepa Silva
    • 5
  • Arifa N. Naqvi
    • 6
  • Rahamame Sanfo
    • 7
  • Racine-Samba Sow
    • 8
  • Baitsi Podisi
    • 9
  • Cliona O’Farrelly
    • 3
  • Olivier Hanotte
    • 10
  • Daniel G. Bradley
    • 1
  1. 1.Smurfit Institute of Genetics, Trinity CollegeUniversity of DublinDublinIreland
  2. 2.Department of Molecular Biology and BiochemistrySimon Fraser UniversityBritish ColumbiaCanada
  3. 3.School of Biochemistry and Immunology, Trinity CollegeUniversity of DublinDublinIreland
  4. 4.Bangladesh Agricultural UniversityMymensinghBangladesh
  5. 5.University of PeradeniyaPeradeniyaSri Lanka
  6. 6.PARCIslamabadPakistan
  7. 7.INERAOuagadougouBurkina Faso
  8. 8.ISRADakarSenegal
  9. 9.Department of Agricultural ResearchGaboroneBotswana
  10. 10.International Livestock Research InstituteNairobiKenya