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#16
A WEB-BASED SYSTEM FOR PROGNOSTIC ALLELE LEVEL HLA-DRB1-MATCHING IN WORLD-WIDE UNRELATED DONOR SEARCH.
Ulrike Feldmann 1, Werner Bochtler M.Sc. 1, Hans-Peter Eberhard M.Sc. 1 and Carlheinz R. Mueller M.D.,Ph.D. 1. 1 ZKRD, Zentrales Knochenmarkspender-Register Deutschland, Ulm, Germany .
Most active unrelated stem cell donor registries in the world are participating in the cooperation of Bone Marrow Donors Worldwide (BMDW). Formally BMDW is a service provided by the Dutch registry Europdonor collecting all data, providing them back to the contributors and making them directly accessible via a web based matching program. Unfortunately, HLA information is limited for many donors in particular where DRB1 alleles are missing or only tested at low or intermediate resolution.
We are using our own copy of the BMDW data to generate haplotypes frequencies per registry for HLA-A,B,DRB1. HLA-A and B are analyzed using serological nomenclature and DRB1 using a resolution of 2 and 4 digits as far as the data for each registry permits. These haplotypes frequencies are used for a web based system prototyped in our intranet which calculates the probability of finding a donor who is a match for HLA-A and B (serology) and for DRB1 (allele level) by performing subsequent test on partially typed donors. In the calculation of the conditional match probabilities the program correctly interprets all broad serological designations and multiple allele codes using the individual frequencies for each registry.
Where there are test candidates in several registries the system can also indicate which donors according to there origin or partial typing status are most likely to turn out to be matches. This provides a highly intelligent sorting of BMDW match lists. The program is currently implemented as a CGI-script using PERL and typically takes 5-20 seconds on a 1.5 GHz XEON including a full molecular BMDW match run.
The program has immediately become an indispensable tool for the analysis of all difficult donor searches.