Background: Matching the compatibility of donor blood with the recipient's antigens prevents alloimmunisation. Next-generation sequencing (NGS) technology is a promising method for extensive blood group and platelet antigen genotyping of blood donors. It circumvents the limitations of detecting known alleles based on predefined polymorphisms and enables targeted sequencing on a massive scale. The aim of this study was to evaluate the NGS AmpliSeq application on the Ion Torrent platform as a screening tool for genotyping blood donors' erythrocyte/platelet antigens.
Materials and methods: Primers for regions encoding antigens RhD (exons 5, 7), Rhc, RhE/e, Fya/b, Jka/b, M/N, S/s, HPA-1, 2, 3, 5, 15 were designed with Ion AmpliSeq Designer with manual inclusion of RHCE*C primers. DNA libraries of 57 regular blood donors with determined phenotype/genotype (prepared using the Ion AmpliSeq Library Kit and 14 primer pairs) were sequenced on the Ion Torrent PGM using 316v2 chips and 200 bp chemistry.
Results: Sequencing was successful in all but the MN and HPA-5 regions. Mean sequencing coverage in one experiment was 4,606 reads, except for the RHCE*C region (mean 568 reads). NGS results agreed with the known phenotype/genotype of donors except in one phenotypically Fy(a+b-) case in whom FY*A/FY*B alleles were found. Reading rates for homozygotes were 97-100%, while they were around 50% for heterozygotes. NGS of RHD regions led to identification of mutations in two RhD negative donors.
Discussion: NGS can be performed as a screening test to determine erythrocyte/platelet antigens in blood donors. This method allowed testing of 48 donors for 14 features (200 bp long) with the depth of a few thousand reads simultaneously, and the estimation of natural chimerism or hemi/homozygotic status. NGS screening can be adjusted to the genetic background of a given tested population.