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

Biol Blood Marrow Transplant. 2016 Nov;22(11):2038-2046. doi: 10.1016/j.bbmt.2016.07.022. Epub 2016 Aug 2.


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.

Keywords: Cord blood unit selection; Donor selection; HLA matching; Predictive algorithm.

Publication types

  • Validation Study

MeSH terms

  • Algorithms*
  • HLA Antigens / immunology
  • Hematopoietic Stem Cell Transplantation / methods*
  • Hematopoietic Stem Cells / immunology
  • Histocompatibility Testing / methods*
  • Humans
  • Unrelated Donors


  • HLA Antigens