Tag SNPs for HLA-B alleles that are associated with drug response and disease risk in the Chinese Han population.

Multiple HLA-B alleles (haplotypes) are associated with drug-induced adverse responses and disease risks but are difficult to be directly genotyped. The goal of this study is to identify single nucleotide polymorphisms (SNPs) that are able to tag HLA-B alleles in the Chinese Han population. Twelve HLA-B alleles that are associated with drug adverse responses and disease risks were identified. They were sequenced initially in 880 Chinese Han subjects where high-density SNPs within the HLA-B gene were available. Performances of these SNPs to tag the HLA-B alleles were assessed primarily by sensitivity and specificity. Two HLA-B alleles can be reliably tagged by SNPs at 100% sensitivity and >95% specificity. For example, HLA-B15:02 can be tagged by the 'C' allele of rs10484555, and HLA-B58:01 can be tagged by the 'T' allele of rs9262570. These results were confirmed in 500 additional Chinese Han subjects. If confirmed in independent studies, these tag SNPs could be used as a reliable, simple and cost-effective alternative for genotyping a subset of HLA-B alleles.