8.416667
#34-OR
FREQUENCIES OF HUMAN MINOR HISTOCOMPATIBILITY ANTIGENS AND ALLELES DETERMINED USING A NOVEL LUMINEX GENOTYPING ASSAY.
Thomas M. Ellis ¹, Melissa B. Warden ¹, Karen L. Pierce ¹, Brian K. DuChateau ¹ and Bradley C. Pietz ¹. ¹ The Histocompatibility and Immunogenetics and Product Development Laboratories, The Blood Center of Wisconsin, Milwaukee, WI .

---

Minor histocompatibility antigens (mHA) induce T cell-mediated immune responses that may contribute to increased risk of graft versus host disease and graft versus leukemia effects. Unlike HLA genes, mHA are encoded by genetically and functionally unrelated genes located throughout the chromosome. The role of mHA in stem cell transplantation and the population frequencies of mHA alleles remain unknown due in part to the lack of suitable high throughput methods for genotyping these diverse genes. Here we describe the development and utility of a multiplexed Luminex assay for genotyping human mHA, including HA-1, HA-2, HA-3, HA-8, HB-1, CD31¹²⁵, and CD31⁵⁶³. The assay utilizes a multiplexed, allele-independent gated amplification of mHA genes followed by differential detection of allele-specific primer products using the MultiCode system (Eragen Biosciences, Madison, WI). The alleles are interrogated using a multiplex allele-specific primer extension reaction using primers tagged with EraCodes, the products are hybridized to Luminex beads, and the hybridization duplexes detected using streptavidin-PE. The assay resolved mHA genotypes of 259 Caucasian donors, providing population estimates of mHA gene and phenotypic frequencies. All mHA alleles evaluated in this study exhibited Hardy-Weinberg equilibrium, although some mHA phenotypes were infrequent (HA2^-, HB-1^-). We anticipate this assay will provide a valuable tool for determining mHA frequencies in other ethnic populations, as well as for establishing the clinical importance of mHA disparities in stem cell transplantation.