Educational webinars
| Feature | Optimatch | HAP-E | ATLAS |
|---|---|---|---|
| AB search | Yes (separate search) | No. Technically possible, but turned off for performance reasons. | No. Not possible because donors without DRB1 are not accepted by ATLAS as valid donors. |
| ABDR search | Yes | Yes | Yes |
| AB Antigen, DRB1 allele match (for cord matching) | Yes | Yes | Not planned. Lack of community interest. requires fundamental code changes. |
| Sorting performed by Matching Engine | Yes | No. WMDA Search and Match performs sorting. | Yes, but WMDA will override with own sort parameters |
| Information about probability of match at other allele at already mismatched locus | No | Yes | Yes |
| Flexible scaling to accommodate periods of high and low use of the engine | No | Yes | Yes |
| g group level matching | Yes | Yes | Yes (actually "P" group matching) |
| G group level matching (leading to less populations and lesser performance for some of populations, but better matching for other populations). | No | No | Yes, but turned off at the moment in favour of g group matching. |
| automatic refresh of patient searches | Yes | Yes | Yes |
| differential results from matching algorithm. → algorithm tells what has changed. | No | Yes | Yes |
| HLA validation of DRB3, DRB4, DRB5, DQA1 and other loci not considered for matching | Possible in Optimatch. Not implemented in WMDA setup for Search & Match v1. | Yes | Loci other than A, B, C, DRB1, DQB1 and DPB1 are not validated or imported by ATLAS and therefore also not returned. |
| Performing a mismatch search will return also (potentially) matched results | Yes | Yes | Yes |
| Consider combination of serological and DNA typing for match probability | Yes | No | No |
| support for > 2 mismatches | Possible in Optimatch. Not implemented in WMDA setup for Search & Match v1. | Not yet. Will also be 2 or more mismatches on ABDRB1. >=4/8 all loci to be considered need to be typed at high resolution for patient. | yes, but only for cords >= 4/8 |
| HLA imputation based on patient organisation and/or pool | Possible in Optimatch. Not implemented in WMDA setup for Search & Match v1. | Yes. | Available at go-live. |
| mismatches per locus can be sent directly to matching engine? | Yes, during actual search and during retrieval. | No. Server side filtering needed for API and GUI | Yes, but not fast. For performance reasons WMDA will perform server side filtering for GUI use. |
| null allele handling | Only considers null alleles with allele frequency higher than 0% in donor population or high resolution null allele. | Will return donors which match haplotype with known null allele or high resolution null allele. | ? |
| TCE handling for DPB1 | Allele frequency based TCE3 | Allele frequency based TCE3 The determination of permissiveness follows the logic described in Crocchiolo et al., 2009. The TCE group assignment is based on functional distances as described in Crivello et al., 2016 | TCE3 |
| match grade handling when multiple potential ARDs in donor typing | When only 1 ARD in ambiguity list occurs in the known haplotypes → allele match ("A") | Always "Potential" even if there is only 1 ARD in known haplotypes (100% potential match) | |
| broad serology level matching | yes | No. Split serology will only match same split serology or when donor/patient is broad serology. Not matched when patient/donor has split serology that is different but both share same broad serology. e.g.
| AB Antigen, DRB1 allele match not supported. |
| Lowest probability in search results | 1 (0 is very rare circumstances). 0% match probability for haplotype frequency matching displayed as 1% if allele frequency based matching indicates possible match. | 0 | 0 |
| matching probability when donor haplotype cannot be explained | No match probabilities displayed. | No match probabilities displayed. | No match probabilities displayed. |
| directionality of DPB1 nonpermissive mismatch indicated? | Yes | Yes | Yes |
| Indicate in search result that it is unclear whether allele or antigen mismatch | Yes | No | No |
| donors returned with A, B and C and/or DQB1, but not DQB1 | Yes in AB search | yes but filtered out | donors without DRB1 are never returned |
| HLA typing other than A, B, C, DRB1, DQB1 and DPB1 (e.g. DRB3/4/5 or DPA1) available in search results and full report | Yes | yes, only in full report due to design choice in Search & Match | no. |
| Meaning of locus-specific match probability | Locus match probability no matter the amount of overall mismatches | Locus match probability in the case of additional mismatch | Locus match probability no matter the amount of overall mismatches |
| Handling of "NEW" alleles (alleles that do not yet have an official allele name). See https://onlinelibrary.wiley.com/doi/10.1111/tan.15048 | ? | Supported for Donors and Patients. Search & Match including Dataupload currently only supports NEW alleles for Patients (so Search & Match). | Not currently supported. Support will be added in the future using ticket https://github.com/Anthony-Nolan/Atlas/issues/876 |
| Homozygous mismatch: how many mismatches | Configurable. Currently set to "2" in WMDA Search & Match. | 2? |