In the Japanese population we identified PTGER3 as a susceptibility gene for CM-SJS/TEN with SOC (8), and we reported that HLA-A*02:06 and PTGER3 polymorphisms exerted additive effects in Japanese and Korean patients with CM-SJS/TEN with SOC (OR = 10.8 and 14.2, respectively) (46). This evidence concerns the gene HLA-A and toxic epidermal necrolysis.