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titleWhy is a matching donor who is typed at higher resolution listed after donors typed at lower resolution?

This can happen only if the difference in resolution is not considered sufficiently relevant in the given context by Hap-E Search and ATLAS. Below are some possible (not mutually exclusive) reasons:

  1. The allele designations encode for the identical ARD (Antigen Recognition Domain) and Hap-E Search and ATLAS only matches for the ARD part of the HLA protein complex. For example B*07:ANVB stands for B*07:02/07:61 which both encode for the same ARD (here: exon 2 and 3). Hence Hap-E Search and ATLAS is regarding the codes B*07:02, B*07:61 and B*07:ANVB all as allele matches for each other but might give different matching probabilities for phenotypes containing each of those three codes since haplotypes involving B*07:02 and B*07:61 are having individual frequencies.
  2. The resolution only looks higher but, in fact, is lower (e.g.  B*15:14 currently is only a single allele while B*15:14:01G covers three), identical (e.g. A*80:01, A*80:01:01 and A*80:01:01G cover exactly the same alleles) or not directly comparable since each code is containing some alleles not covered by the other (e.g. comparing  B*07:TDVB and B*07:02:01G the former also covers a lot more variants of  B*07:02 like  B*07:02:02 to B*07:02:05 while it is excluding other alleles like B*07:44 and B*07:49N).
  3. The broader code only contains additional alleles which have never  been observed in the population whose haplotype frequencies are used - at least not in a relevant haplotypical context. Their frequency could also be so low that it is disregarded due to rounding or the 10%  probability grouping explained elsewhere. This applies, in particular, to all null variants of expressed alleles with identical first two field designations.


CASE STUDIES


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titleWhy do I see two alleles in bold on a locus in the one mismatch(9/10) category?

In rare cases the match program cannot decide which of two B locus results are a mismatch, in those cases both are given in bold. For example, the patient is B*27:05, 44:03; the donor is B*44:ABYM, 44*AFFK. In this case both multiple allele codes include 44:03 therefore the match program cannot choose between them. See example image below where donor 12 on the search report is being marked as having two HLA-B mismatches, when actually it is only a single mismatch.

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CASE STUDIES

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titleWhy, despite complete patient HLA, can only a 6/6 but not a 10/10 search report be generated?

The patient's 5 locus phenotype (10/10) cannot be explained by the haplotypes used for probability matching. The algorithm tries to fall back to 4 locus phenotypes (8/8) and 3 locus phenotypes (6/6).

By default the system should run a 10/10 matched donor run. Why do I get only 8/8 or 6/6 results?
  • If the HLA of the patient
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titleBy default the system should run a 10/10 matched donor run. Why do I get only 8/8 or 6/6 results?
  • The patient's 5 locus phenotype (10/10) cannot be explained by the haplotypes used for probability matching. The algorithm tries to fall back to 4 locus phenotypes (8/8) and 3 locus phenotypes (6/6).
  • If the HLA of the patient does not contain information for all 5 loci, the system will automatically scale the match run down to 8/8 or 6/6 depending on the available HLA information of the patient.

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titleWhy does a DQ mismatch donor not show for my patient under the 8/8 donor list?

Currently, 10/10, An 8/8 and 6/6 lists are reserved for donors that have no known mismatches. Donors that have known mismatches for your patients will only be returned when you select "Run a Mismatch Search" and then select to view a 9/10 or 7/8 match type results list.search does not consider DQB1 and therefore will not show whether a donor has or does not have a mismatch for DQB1. If the donor only has a known mismatch at DQB1, this donor will show up in the search results as a potential 8/8 match. 

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titleHow does WMDA handle A*02:01 vs *02:03. Antigen =\ or allele =\. Another example is B* 15:01 vs 15:03.

A*02:01 (2) vs. 02:03 (203) is an allele mismatch because A203 is an associated antigen to A2.

B*15:01 (62) vs. B15:03 (72) is an antigen mismatch.

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