Mapping of susceptible variants for cold medicine-related Stevens–Johnson syndrome by whole-genome resequencing

Stevens–Johnson syndrome (SJS) and its severe condition with extensive skin detachment and a poor prognosis, toxic epidermal necrolysis (TEN), are immunologically mediated severe cutaneous reactions of the skin and mucous membranes such as the ocular surface. Genetic variations on the HLA-A and other autosomal genes have been identified as risk factors for cold medicine-related SJS/TEN with severe ocular complications (CM-SJS/TEN with SOC). Using a whole-genome sequencing (WGS) approach, we explored other susceptible variants of CM-SJS/TEN with SOC, especially among rare variants and structural variants (SVs). WGS was performed on samples from 133 patients with CM-SJS/TEN with SOC and 418 healthy controls to obtain single nucleotide polymorphisms (SNPs) and SVs. Genome-wide association tests were performed with these variants. Our genome-wide association test reproduced the associations of the common variants of HLA-A and loci on chromosome 16q12.1. We also identified novel associations of SVs on these loci and an aggregation of rare coding variants on the TPRM8 gene. In silico gene expression analysis on the HLA-A locus revealed that the SNP (rs12202296), which was significantly associated with susceptibility to CM-SJS/TEN with SOC, was correlated to an increase in HLA-A expression levels in the whole blood (P = 2.9 × 10⁻¹⁷), from the GTEx database. The majority of variants that were significantly associated with CM-SJS/TEN with SOC were found in non-coding regions, indicating the regulatory role of genetic variations in the pathogenesis of CM-SJS/TEN with SOC.