Refined information on alleles belonging to the C*07:01/07:06/07:18 group in the Korean population.

Alleles of the C*07:01/07:06/07:18 group is distinguished by polymorphisms in exons 5-6. In a previous study, we focused on exons 2-3 of the gene and showed that 6.8% of Koreans express alleles in this group. In this study, we identified allelic and haplotypic diversities of the C*07:01/07:06/07:18 group in Koreans. Among 118 C*07:01/07:06/07:18-positive, unrelated, healthy samples, 96.6% were C*07:06 and 3.4% were C*07:01. Each allele was exclusively associated with a specific set of other alleles consisting of the conserved haplotypes A*01:01-C*07:01-B*08:01-DRB1*03:01-DQB1*02:01 (100%) and A*33:03-C*07:06-B*44:03-DRB1*07:01-DQB1*02:02 (95.6%), respectively. None carried C*07:18. With the continuous discovery of novel alleles, periodic updates with testing for newer alleles will be useful to support related research and clinical settings in each population.

Additional sequence analysis outside exon 2 clarifies DRB1*12 and DRB1*14 allelic frequencies in Koreans.

Polymorphisms outside exon 2 of the DRB1 coding region exhibit increased ambiguities in allele assignments in typing laboratories analyzing the exon 2 sequence alone. This study investigated the frequencies of alleles in DRB1*120101/1206/1210 and DRB1*140101/1454 groups by DNA sequencing of exons 1 and/or 3 and examined their associations with class II alleles at adjacent loci in Koreans. Of 103 individuals, 97 were DRB1*120101 and 6 were DRB1*1210. None carried DRB1*1206, an allele initially characterized from a Korean individual. Association of DRB1*120101 with various DRB3, DQA1, and DQB1 alleles was reflected in 11 different four-locus haplotypes. In contrast, DRB1*1210 was exclusively associated with DRB3*020201, DQA1*0505, and DQB1*0301. All 97 DRB1*140101/1454 samples were DRB1*1454. DRB1*1454 was strongly associated with DRB3*020201, DQA1*010401, and two different DQB1 alleles (*0502, *0503). Continuous updating of HLA high-resolution typing information will be useful in the development of typing and matching strategies for hematopoietic stem cell transplantation.