DETECTION OF 14 HLA-DQB1 ALLELES BY OLIGOTYPING

Fourteen alleles have been identified by analysis of the nucleotide sequences encoding the HLA-DQB1 chain. This study describes the detection of these 14 alleles by selective gene amplification and sequence-specific hybridization with nonradioactive oligonucleotide probes. These techniques were employed to create an oligotyping system with two levels of resolution that provide versatility and the capacity for comprehensive detection of all polymorphic sequences. An initial low-resolution assay was employed to detect four major groups of alleles that are associated with the DQw1-w4 serological specificities. A further high-resolution assay was then employed to differentiate 14 individual DQB1 alleles. Appropriate control measures were also included to detect carry-over and to confirm hybridization specificity. This system was used to analyze the allele frequencies of DQB1-0301, -0302, and -0303 in 115 DQB1-03** Caucasian blood donors. Allele frequencies of oligotypes DQB1-05** and DQB1-06** were analyzed in 112 DQB1-01** Caucasian blood donors. This system was also utilized to identify oligotypes designated DQB1-0501 through DQB1-0503 and DQB1-0601 through DQB1-0605 in 35 Tenth International Histocompatibility Workshop DQw1 cell lines to examine the correlation with serological and cellular specificities. In one of these cell lines, an unexpected linkage was discovered between the DRB1 and DQB1 loci, suggesting a recombination event. Oligotyping is a precise and accurate method for directly defining polymorphic sequences and it promises to have a major impact on the future direction of HLA typing.