Jane Kempenich

HapLogic: A Predictive Human Leukocyte Antigen-Matching Algorithm to Enhance Rapid Identification of the Optimal Unrelated Hematopoietic Stem Cell Sources for Transplantation.

The search for a suitable human leukocyte antigen (HLA)-matched unrelated adult stem cell donor (URD) or umbilical cord blood unit (UCB) is a complex process. The National Marrow Donor Program (NMDP) developed a search algorithm known as HapLogic, which is currently provided within the NMDP Traxis application. The HapLogic algorithm has been in use since 2006 and has advanced URD/UCB HLA-matching technology. The algorithm has been shown to have high predictive accuracy, which can streamline URD/UCB selection and drive efficiencies in the search process to the benefit of the stem cell transplantation community. Here, we describe the fundamental components of the NMDP matching algorithm, output, validation, and future directions.

16th IHIW: Extending the number of resources and bioinformatics analysis for the investigation of HLA rare alleles

Continuing a project presented at the 15th International HLA and Immunogenetics Workshop (IHIWS) on the rarity of HLA alleles, we sought to expand the number of data sources and bioinformatics tools available in the Allele Frequencies Net Database website (AFND, www.allelefrequencies.net). In this 16th IHIWS Rare Alleles project, HLA alleles described in the latest IMGT/HLA Database (release 3.8.0) were queried against different sources including data from registries (stem cell) and from 74 different laboratories around the world. We demonstrated that approximately 40% of the alleles officially named in the IMGT/HLA Database have been reported only once across all different sources. To facilitate the large‐scale analysis of rare alleles, we have produced an online tool called the Rare Allele Detector that simplifies the detection of alleles that are considered to be ‘very rare’, ‘rare’ or ‘frequent’. Tools and associated data can be accessed via the www.allelefrequencies.net website.

Unrelated donor HLA re‐typing effort to verify prevalence of newer alleles: HLA‐A*24:23, A*30:10, DRB1*08:11, DRB1*15:03, and DRB1*15:06

The National Marrow Donor Program (NMDP) is committed to maintaining accurate human leukocyte antigen (HLA) data for each of the 11.5 million volunteer donors on the Be The Match Registry(®) . Qualitative data analysis identified five population specific alleles suspect of being incorrectly characterized. Alleles evaluated were HLA-A*24:03 for the presence of A*24:23 in Native Americans, A*30:02 for the presence of A*30:10 when B*41 and DRB1*04:05 were in the haplotype, DRB1*08:02 for the presence of DRB1*08:11 in Native Americans, and DRB1*15:01 for the presence of DRB1*15:03 in African Americans or DRB1*15:06 in Asian donors. Discrepancy rate was 55%, 86%, 31%, 75%, and 13%, respectively. Utilizing the HLA typing date, race, and date an allele in question was described may provide a selection strategy leading to the consideration of additional unrelated donors for searching patients.