Among the 1793 presumably new alleles detected by the analysis software, 11 displayed exon mismatches, of which 9 were confirmed as new alleles and 2 had been described previously. We observed only seven (0.1%) critical mistakes among the 6009 alleles typed, corresponding to two allele dropouts, one false heterozygous typing assignment and four phasing abnormalities. We performed 15 runs between April and September 2018 to type DNA at the HLA‐A/B/C/DRB1/3/4/5/DQA1/DQB1/DPA1/DPB1 loci from 340 samples and 15 positive controls. Reads were analyzed using the TypeStream Visual software. We aimed at evaluating the performance of the One Lambda AllType kit using Thermo Fisher Scientific reagents on the Ion S5 XL platform. HLA genotyping by next‐generation sequencing is now widely performed. This study has demonstrated high‐resolution typing by NGS can be achieved in an acceptable turnaround time for a clinical laboratory however, the Ion Torrent workflow has some technical limitations that should be addressed. However, some limitations were observed primer locations did not allow all ambiguities to be resolved for HLA Class II where Exon I and IV amplification are needed (HLA‐DRB1*04:07:01/04:92, HLA‐DRB1*09:01:02/*09:21 and HLA‐DRB1*12:01:01/*12:10). A turnaround time of four days was achieved for typing 44 samples. Concordance rates of 91%–98% were obtained (for HLA‐A, ‐B, ‐C, ‐DRB1, ‐DQB1 and ‐DPB1) when compared to historical PCR‐SSO HLA types, and the identification of uncommon alleles such as A*24:07:01 and C*04:82 were observed. A total of 362 registry donors from four ethnic populations (Europeans, South Asians, Africans and Chinese) were NGS HLA typed across 9‐loci (HLA‐A, ‐B, ‐C, ‐DRB1,‐DRB345 ‐DQB1 and ‐DPB1). In this study, the One Lambda NXType NGS kit was tested on the Ion Torrent PGM platform. NGS has provided a rapid, high‐resolution HLA typing solution, which has reduced the number of HLA ambiguities seen with other typing methods. Within a clinical laboratory, a technique for high‐resolution HLA typing, which is rapid and cost effective is essential. The development of techniques to define the human leucocyte antigen (HLA) region has proven to be challenging due to its high level of polymorphism.
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