rs9263726 is a specific genetic marker for allopurinol-induced severe cutaneous adverse reactions in Chinese patients.

Objective: Screening of an easily detectable biomarker to replace the HLA allele B variant (HLA-B*58:01) testing for predicting allopurinol-induced severe cutaneous adverse reactions (SCARs) in eastern Chinese patients.

Methods: Six SNPs and the HLA-B*58:01 were analyzed in 17 patients with allopurinol-induced SCARs and in 151 control patients. SNPs were analyzed by pyrosequencing, and HLA-B*58:01 was evaluated by sequencing-based techniques. Consistency between sequencing-based HLA-B*58:01 testing and pyrosequencing-based rs9263726 testing was investigated in 262 individuals.

Results: A significant association with allopurinol-induced SCARs was found at rs9263726 (odds ratio: 108.8) and HLA-B*58:01 (odds ratio: 108.8). The kappa values between sequencing-based HLA-B*58:01 testing and pyrosequencing-based rs9263726 testing were 0.96 (>0.75), demonstrating they were well coincident with each other.

Conclusions: rs9263726 was a useful surrogate of HLA-B*58:01 testing for prescreening allopurinol-induced SCARs in eastern Chinese patients.