Thank you for visiting the IPD-MHC OLA sequence website. This site is intended to provide a source of information on the ovine leukocyte antigen (OLA) complex, the Major Histocompatibility Complex of domestic sheep Ovis aries as well as other species within the genus Ovis. This site is encouraged and supported by the comparative MHC steering committee of the International Society for Animal Genetics. Its purpose is to collate data on the ovine leukocyte antigens and to provide a forum for the analysis, verification and nomenclature of allelic polymorphisms in the genes and proteins of the ovine MHC.


We have listed currently known alleles which meet the criteria described in the Nomenclature rules page. New nomenclature is used where possible, and tables of previous equivalents are given. Accession numbers and references for published sequences are also listed.

For more information on OLA nomenclature pleases contact;

  • Dr Keith Ballingall keith.ballingall@moredun.ac.uk Moredun Research Institute Pentlands Science Park, Bush Loan, Penicuik Midlothian, EH26 0PZ Scotland, UK Tel: +44 (0) 131 445 5111 ext 161
  • Prof Mike Stear m.j.stear@vet.gla.ac.uk Department of Veterinary Medicine, Glasgow University Glasgow, G61 1QH Scotland, UK Tel: +44 (0) 141 330 5762

Above are listed the most populated genes within the Ovids group. To list all the genes within the OLA taxonomic group, please visit the species page.

Search OLA alleles

Examples: Mafa, A1*01:01 advanced search

Group curator

Dr. Keith Ballingall - keith.ballingall [at] moredun.ac.uk

Moredun Research Institute, Unknown, United Kingdom


  • Maccari G, Robinson J, Ballingall K, Guethlein LA, Grimholt U, Kaufman J, Ho CS, De Groot NG, Flicek P, Bontrop RE, Hammond JA and Marsh SGE IPD-MHC 2.0: an improved inter-species database for the study of the major histocompatibility complex. Nucleic Acids Res. (2017), 45: D860–D864
  • Ballingall KT, Herrmann-Hoesing L, Robinson J, Marsh SGE, Stear MJ A single nomenclature and associated database for alleles at the major histocompatibility complex class II DRB1 locus of sheep Tissue Antigens (2011), 77:543-56