HCP5 and toxic epidermal necrolysis: Although the associated haplotype was in linkage disequilibrium with the HLA-B*58:01 allele, the findings of this GWAS provided insightful information regarding the potential association of allopurinol-induced SJS/TEN with other possible genes e.g. HCP5, PSORS1C1 and POU5F1, in addition to HLA-B [12].