Application of RSCA for the typing of HLA-DPB1

We describe the application of RSCA, for the high resolution typing of alleles encoded at the HLA-DPB1 locus. RSCA differs from other sequence based typing methodologies in that the HLA type is assigned on the basis of differences in DNA conformation between different alleles. A total of 251 samples were typed in a blind study, of these 109 samples had been typed previously by conventional techniques. A comparison of the RSCA data with the historical typing results showed a concordance over 93%. Seven samples initially had discordant results, however, when these samples were typed by direct sequencing, the type assigned by RSCA was found to be correct in all but one case, indicating a concordance over 99%. RSCA has proved to be a simple reliable technique for the typing of the HLA-DPB1 locus, and is not limited by the ambiguous combinations of alleles determined in other conventional techniques.