[Establishment of allele specific primer polymerase chain reaction sequence-based typing and investigation of the polymorphism in exon 3 of HLA-DRB1]

To establish the allele specific primer polymerase chain reaction sequence-based typing (PCR-SBT) and investigate the polymorphism of exon 3 of human leukocyte antigen( HLA)-DRB1.The fragment containing exons 2 and 3 of HLA-DRB1 gene was amplified by group specific primers. The amplified products were digested by restriction enzymes and directly sequenced in both directions. The genotype was assigned by using Assign 3.5 SBT software.The exon 3 sequences of HLA-DRB1*08:09 and HLA-DRB1*12:02:01 were identified for the first time. There were 27 polymorphic sites in exon 3 among the twenty-five HLA-DRB1 alleles, which was 9.56% of all nucleotides of exon 3. The method could discriminate the HLA-DRB1*14:01:01/14:54 ambiguous samples, and the HLA-DRB1*14:01:01 was identified in the Chinese population.The PCR-SBT method for exon 3 of HLA-DRB1 from the present study was reliable and there were polymorphisms in exon 3 of HLA-DRB1.