HLA-B*58:01

What is HLA-B*58:01?

HLA-B*58:01 is a variant of a human leukocyte antigen (HLA) gene, the system the immune system uses to present fragments of proteins — including drugs bound to proteins — to T cells. Particular HLA alleles bind particular drugs, which is why carrying one can turn an ordinarily safe medicine into a severe immune reaction, and why some alleles track autoimmune conditions.

Particularly important for East Asian populations where HLA-B*58:01 frequency is highest. Allopurinol-induced SJS/TEN has ~25% mortality rate.

How common is HLA-B*58:01?

Drug reactions linked to HLA-B*58:01

Allopurinol Hypersensitivity (SJS/TEN/DRESS) high risk

HLA-B*58:01 carriers should NOT be prescribed allopurinol. Use febuxostat or other urate-lowering therapy instead. FDA label recommends HLA-B*58:01 testing before initiating allopurinol, especially in patients of Southeast Asian, African American, or Korean descent.
Evidence: CPIC Level A (Strong); FDA Label Warning · Source: CPIC Guideline for Allopurinol and HLA-B (2015, updated 2024) · HLA-B*58:01 prevalence: ~6-8% in Han Chinese, ~3.8% in Korean, ~3.8% in African American, ~1-2% in European.

How is HLA-B*58:01 inferred from a consumer DNA file?

Consumer chips do not sequence HLA genes. HLA-B*58:01 is inferred from the tag SNP rs9263726 (risk allele C), which travels with the HLA allele on the same stretch of chromosome. How reliably it does so (r²) differs by ancestry:

A tag-SNP call is a probability, not a laboratory HLA type. A positive result that would change a prescription should be confirmed by clinical HLA typing.