Scheme Description
UK NEQAS for H&I are aware that many H&I laboratories use DNA techniques only for HLA typing, but that results often have to be ‘interpreted’ to the appropriate specificity (e.g. DQB1*03:01 group ‘interpreted’ as DQ7) during routine laboratory work.
This may be required for;
- Donor specific antibody analysis
- Deceased donor HLA typing reports for National Organ Allocation
- HLA associated disease reports
- Identification of potential unrelated haematopoietic stem cell donors in registry databases which may have been typed using serology
Participants are requested to report results using the correct nomenclature https://hla.alleles.org/.
See also: R. Holdsworth, C.K. Hurley, S.G.E. Marsh, M. Lau, H.J. Noreen, J.H. Kempenich, M. Setterholm, M. Maiers. A summary of HLA-A, -B, -C, -DRB1/3/4/5 and -DQB1 alleles and their association with serologically defined HLA-A, -B, -C, -DR and -DQ antigens Tissue Antigens. 2009, 73:95-170
Purpose
To assess participants’ ability to correctly interpret their Scheme 4A1 DNA based typing results to the ‘split’ HLA specificity level. Note that Scheme 4A1i is only available to participants registered for Scheme 4A1.
Samples
Results from participants’ HLA typing at the first field level for Scheme 4A1 will be used as the basis for interpretation.
Reporting
Participants may register for interpreted specificity assessment for any of the following: HLA-A, B, Cw, DRB1, DQB1 or ‘presence of’ assessment for Bw4/6 and DR51/52/53.
Participants must only use the reporting forms provided within the UK NEQAS for H&I Participant’s Portal and return results within 2 weeks.
Participants are requested to report ‘interpreted’ results to the split specificity level where appropriate (e.g. B*40:01 allele group as B60, DQB1*03:01 group as DQ7, C*03:03 allele group as Cw9) using the correct nomenclature https://hla.alleles.org/.
The Steering Committee acknowledge that there are HLA alleles/allele groups with no specificity equivalent and these may be reported as e.g. B15, B40. The Steering Committee also acknowledge that HLA-C alleles above C*10 do not have a recognised specificity, but these should still be reported as the HLA phenotype e.g. Cw16. Null alleles should be reported using the suffix ‘N’ e.g. Cw4N if a definitive definition of a null allele has been made.
Please do not report Bw4 for associated HLA-A specificities.
Assessment
Participating laboratories will be assessed on the loci they designate at registration.
The consensus full HLA type is determined by at least 75% of laboratories agreeing each specificity. A “blank” forms part of the assessment if at least 75% of laboratories report a single specificity at a locus. A reference result will be used for assessment for samples failing to reach the 75% consensus level (see section 10.5).
Scheme 4A1 results form the basis for Scheme 4A1i interpretation. Therefore samples with results that are deemed ‘unacceptable’ for Scheme 4A1 will not be assessed in Scheme 4A1i.
Assessment Procedure
Each full HLA type in agreement with the consensus/reference HLA type – Acceptable
Each full HLA type not in agreement with the consensus/reference HLA type – Unacceptable
Each sample/registered loci not reported – with valid reason – Not Assessed
Each sample assessed as ‘unacceptable’ in Scheme 4A1 – Not Assessed
Each sample /registered loci not reported / late submission – Unacceptable
Satisfactory Performance
Satisfactory performance is obtaining nine or more full HLA types in agreement with the consensus/reference HLA types in a year.
Laboratories with unsatisfactory performance will receive written notification of their status and will be expected to reply to UK NEQAS for H&I detailing their corrective actions. For UK laboratories, unsatisfactory performance will be reported to UK NQAAP for Immunology. For UK laboratories, failure to reply or replies deemed unsatisfactory are likely to be further actioned by UK NQAAP for Immunology.
Information/Analysis Provided to Participants
- Anonymised summary table of all participant results, comments and methodology. Including sample assessment result (acceptable/unacceptable classification) for each participant.
- End of year summary of participant performance.