Distributions of HLA-A, -B, -C,-DRB1 and-DQB1 alleles typed by next generation sequencing in Russian volunteer donors

HLA genes play a major role for successful hematopoietic stem cell transplantation (HSCT). While the success of HSCT depends on a HLA compatibility between donor and patient, finding a suitable donor remains challenging because of the high polymorphic nature of HLA genes. In this study, HLA-A, -B, -C, -DRB1 and -DQB1 alleles were genotyped at the 3-fields resolution level using MiSeq Illumina of 3341 Russian volunteers from the Kirov bone marrow Registry. Full gene of HLA-A, -B and -C, exons 2-4 of HLA-DRB1 and exons 1-5 of HLA-DQB1 were amplified by multiplex long-range polymerase chain reaction (PCR) and each allele was determined by matching the targeted regions and the reference sequence consisting of the IPD-IMGT/HLA Database. A total of 79 alleles of HLA-A, 115 alleles of HLA-B, 67 alleles of HLA-C, 71 alleles of HLA-DRB1 and 34 alleles of HLA-DQB1 were identified. According to common, intermediate and well-documented catalogs, 38 alleles in HLA-A, 69 in HLA-B, 39 in HLA-C, 48 in HLA-DRB1 and 21 in HLA-DQB1 locus were common alleles, and 5, 7, 7, 7, 2 kinds, accordingly, to written above were well-documented alleles. A total of 12 novel alleles including 3 alleles in HLA-A, 3 alleles in HLA-B, 1 allele in HLA-C, 2 alleles in HLA-DRB1 and 3 alleles in HLA-DQB1 loci were found. Six haplotypes with a frequency of more than 1.0% accounted for 13.19% of the total haplotype frequencies. This information on rare and novel alleles found by HLA typing with NGS may be helpful for unrelated HSCT among Russians.