RESUMO
Unlike classical HLA class I genes, MR1 is assumed to have limited polymorphic positions. We developed a MR1 specific PCR assay and sequenced 56 DNA samples from cells with a diverse set of HLA genotypes. In this relatively small panel we found six allele groups encoding for different MR1 proteins. The two most frequent allele groups found in this panel had a frequency of 71% (MR1*01) and 25% (MR1*02), respectively. Moreover, the panel contained many intronic SNPs and silent variants, with individual samples containing up to 15 heterozygous positions. The data presented here is consistent with marked variation in MR1.
Assuntos
Antígenos de Histocompatibilidade Classe I , Alelos , Sequência de Bases , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Fases de Leitura AbertaRESUMO
Next Generation Sequencing (NGS) has become a major technology in HLA typing. The expectations are that highly accurate and unambiguous typing results will be obtained. However, HLA typing by NGS has some limitations caused by imperfections in the PCR amplification. The accuracy of NGS data is investigated by analyzing the Short Tandem Repeats (STR) regions. For this analysis HLA-DRB5 is used as the model. The repeat length in a sample highly influences the repeat length distribution present in the reads of NGS data. With a repeat length of 20 only 50% of all reads were of the estimated repeat length, seriously hampering distinguishing allelic differences in this region correctly. Our findings are confirmed by doing the same analysis in HLA-DRB1. Despite the uncertainty of determining the repeat lengths, several new HLA-DRB5 alleles have been identified in this paper.
