There were 3 studies investigating an association between HLA-B*5201 and CM-induced SJS/TEN with SOC in Japanese and Brazilian populations.23,33,34 The numbers of subjects carrying at least one allele of HLA-B*5201 were 14 out of 213 in cases and 139 out of 822 in controls. The gene discussed is HLA-B; the disease is toxic epidermal necrolysis.