Haplotype associations of 90 rare alleles from the National Marrow Donor Program.

The National Marrow Donor Program maintains an HLA database of over 4.1 million US adult volunteers, 43,000 cord blood units, and 111,000 patients from which we identified 1,999,424 samples having allele-level HLA-A, HLA-B, or HLA-DRB1 results. We analyzed 811 rare alleles reported at a frequency of less than 1 in 50,000 in this study pool and found strong predicted haplotype associations for 90 of them. The data set includes the number of times the allele was seen, the predicted haplotypes, and the racial or ethnic groups in which it was identified. This information can be helpful in designing search strategies for patients with rare alleles requiring hematopoietic stem cell therapy.