HLA-DOB1 "low-resolution' typing by PCR amplification with sequence-specific primers (PCR-SSP)

In the study described here primers were designed for DQB1 'low-resolution', i.e. generic, typing by PCR amplification with sequence-specific primers (PCR-SSP) considering all the currently recognized DQB1 alleles, i.e. 0501-0504, 0601-0609, 0201, 0301-0305 and 0401-0402. This resolution was achieved by performing eight PCR reactions per individual. The DQB1 alleles corresponding to the serological specificities DQ4, DQ5, and DQ6 were uniquely identified, whereas the DQ2, DQ7, DQ8 and DQ9 specificities were amplified by two primer mixes. All homozygous and heterozygous combinations of the serological series DQ1 to DQ9 could be distinguished. The yield of amplified products were increased compared to our previously described DQB1 'high-resolution' typing technique by lengthening many of the primers, modifying the PCR cycling parameters and by including glycerol in the PCR reaction mixtures. Thirty-one cell lines and 90 donor spleen cells were investigated by the DQB1 'low-resolution' PCR-SSP technique as well as by TaqI DRB-DQA-DQB RFLP analysis. The concordance between PCR-SSP typing and RFLP analysis was 100%. The cell lines and 20 of the spleen cells were typed twice with complete reproducibility. No false positive or false negative typing results were obtained. DQB1 'low-resolution' PCR-SSP typing, including DNA extraction, PCR amplification, gel detection, documentation and interpretation, were performed in 2 h which renders the PCR-SSP technique suitable also for the genotyping of cadaveric organ donors.