These observations suggest that non-risk HLA-B15 molecules may also support the ligation of certain CBZ-reactive TCRs, implying the association of SJS or TEN with HLA-B*15:02, but not HLA-B*15:01, is not as simple as the ability of the drug to uniquely interact with one HLA allomorph but not another. The gene discussed is HLA-B; the disease is toxic epidermal necrolysis.