1. ¹Department of Oncology, Georgetown University Medical Center, Washington, DC, USA
2. ²National Marrow Donor Program, Minneapolis, MN, USA
3. ³UCLA Immunogenetics Center, Los Angeles, CA, USA
4. ⁴Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA
5. ⁵Fairview-University of Minnesota Medical Center, Histocompatibility Laboratory, Minneapolis, MN, USA
6. ⁶American Red Cross National, Baltimore, MD, USA
7. ⁷ZKRD Zentrales Knochenmarkspender-Register Deutschland (German National Bone Marrow Donor Registry), Ulm, Germany
8. ⁸Canadian Blood Services, Unrelated Bone Marrow Donor Registry (UBMDR), Ottawa, Canada
9. ⁹Department of Surgery, University of Toronto, Toronto, Ontario, Canada
10. ¹⁰Europdonor Foundation and Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
11. ¹¹France Greffe de Moelle, Hospital Saint-Louis, Paris, France
12. ¹²University of Dusseldorf, Dusseldorf, Germany

Correspondence: Dr CK Hurley, E404 Research Building, Georgetown University Medical Center, 3970 Reservoir Road, NW, Washington, DC 20057, USA. E-mail: hurleyc@georgetown.edu

Received 18 May 2003; Accepted 31 July 2003; Published online 15 December 2003.

Abstract

Registries and cord blood banks around the world collect and store the HLA types of volunteers in order to identify matched unrelated donors for patients requiring hematopoietic stem cell transplantation. This task is complicated by the many formats in which HLA types are provided by the testing laboratories (types obtained by serology vs by DNA-based methods; high vs intermediate vs low resolution) and by the need to identify which of these diverse types are most likely to match the HLA assignments of a searching patient as closely as possible. Conversion of the assignments to 'search determinants' may be included within the algorithm used to select and prioritize a list of potentially suitable donors, either as an aid to matching or as a tool to optimize the performance of comparisons within large data files. The strategies used by registries to create search determinants are described. A set of search determinants, utilized by the National Marrow Donor Program, is provided as an example and is intended to initiate further discussion aimed at understanding the process used by each registry with the possibility of developing a standard process among registries worldwide.