[The third-generation sequencing combined with targeted capture technology for high-resolution HLA typing and MHC region haplotype identification].

The high-resolution and accurate typing of human leukocyte antigen (HLA) is of great significance for the study of tissue matching in organ transplantation and the correlation between HLA and disease. In this study, the peripheral blood of 12 patients with primary hepatocellular carcinoma was used to compare the advantages and disadvantages of the next- and third-generation sequencing technology for high-resolution HLA typing. In addition, probe capture technology was used to capture the MHC region of YH and HeLa standard cell lines, and a primary hepatocellular carcinoma patient. The captured products were sequenced using PacBio platform to assess the potential of ultra-long reads sequencing technology for analysis of the entire MHC region. Our results showed that: (1) the next- and third-generation sequencing technology can both achieve 6-8 digit high resolution in HLA typing. However, the coverage of the third-generation is significantly better than the next-generation sequencing technology. (2) The ultra-long reads of the third generation sequencing can directly span the entire amplicon region, which has obvious advantages for haplotype phasing, with 92.79% of the HLA genes having accurate phasing results, which is much higher than the 75.65% from the next-generation data. (3) The long-reads from the third generating sequencing can not only be used to assemble the MHC region but also the ability to phase the entire MHC region of 3.6 Mb, thereby helping to clarify the localization information of the mutation sites, alleles and non-coding regions on each MHC haplotype, and providing a theoretical basis for the study of immune and other related diseases.