The possibility of using the same genotyping technology (TaqMan) for all the genetic tests included in the new Spanish pharmacogenomics portfolio should enable the application of a multigenotyping platform to obtain a whole pharmacogenomics profile. However, HLA-typing is usually performed with other technologies and needs to be adapted to TaqMan assays. Our aim was to establish a set of TaqMan assays for correct typing of HLA-A*31:01, HLA-B*15:02, HLA-B*57:01, and HLA-B*58:01. Therefore, we searched for and selected SNVs described in different populations as surrogate markers for these HLA alleles, designed TaqMan assays, and tested in a set of samples with known HLA-A and HLA-B. HLA-A*31:01 was correctly typed with a combination of rs1061235 and rs17179220 (PPV 100%, 95% CI 84.6–100-%; NPV 100%, 95% CI 96.5–100.0%), HLA-B*15:02 with rs10484555 (PPV 100%, 95% CI 69.2–100.0%; NPV 100%, 95% CI 96.8–100.0%) and rs144012689 (PPV 100%, 95% CI 69.2–100.0%; NPV 100%, 95% CI 96.8–100.0%), and HLA-B*57:01 with rs2395029 (PPV 99.5%, 95% CI 72.9–99.3%; NPV 99.5%, 95% CI 98.3–100.0%). HLA-B*58:01 was typed using two allele-specific TaqMan probes mixed with a ß-Globin reference and treated as a genotyping assay (PPV 100.0%, 95% CI 81.5–100.0%; NPV 100%, 95% CI 96.8–100.0%). In conclusion, we demonstrated a clinically useful way to type HLA-A and HLA-B alleles included in the Spanish pharmacogenomics portfolio using TaqMan assays.
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