When comparing serologies antigen vs allele mismatches are determined as follows.
When comparing DNA typing for both patients and donors, the following rules are applied:
- When serology has been assigned for the DNA typing for both donor and patient, then the logic in the table above is applied.
- When no serology is known the following logic is applied:
- For alleles where no serology exists the allele family is used as a proxy for serology to distinguish between allele and antigen mismatches.
- When HLA-C typing has a first field of higher than 10 → the first field is considered the Antigen
- e.g. HLA-C*12:02 -> 12
- Any HLA-DPB1 mismatch is considered an Antigen mismatch. In HLA-DPB1 all alleles should be treated equally as mismatched, unless using a secondary algorithm, such as one of the TCE models. Therefore, there cannot be any allele mismatches.
The above is based on recommendations that have been approved by the WMDA Bioinformatics & Innovation Committee following discussions with the group, and finalised on 2024-02-07. 2024-02-07 Meeting Notes.