Genome-wide Association Study Identifies Variations in 6p21.3 Associated With Nevirapine-Induced Rash

Background. We aimed to identify disease-predisposing variations with nevirapine-induced rash using genome-wide single-nucleotide polymorphisms (SNPs) as genetic markers. Methods. A genome-wide association study (GWAS) was performed using similar to 550000 markers in 72 human immunodeficiency virus (HIV)-infected Thai patients with nevirapine-induced rash and 77 nevirapine-tolerant patients, and then candidate SNPs were further evaluated in a replication set (88 patients with nevirapine-induced rash and 145 nevirapine-tolerant patients). Results. The genome-wide association analysis and replication studies of candidate SNPs identified significant associations of nevirapine-induced rash with 2 SNPs (rs1265112 and rs746647) within CCHCR1 on chromosome 6p21.3 (P(GWAS) = 1.6 x 10(-4); P(replication) = 2.6 x 10(-5); P(combined) = 1.2 x 10(-8)). The odds ratio (OR) of the risk genotypes under a dominant model was 4.36 (95% confidence interval [CI], 2.58-7.36). The noncoding SNPs rs1265112 and rs746647 were in complete linkage disequilibrium with the nonsynonymous SNP rs1576 (r(2) = 1.00), which has been associated with psoriasis. The logistic regression analysis also indicated genetic variations in CCHCR1 to be significantly associated with rash, with an OR of 2.59 (95% CI, 1.82-3.68; P = .007). The receiver operating characteristic curve showed that the algorithm had an area under the curve of 76.4%, which was developed with 5 factors: rs1576*G status, HLA-B*3505 status, not receiving prescribed lead-in of nevirapine, history of drug allergy, and CD4 cell count prior to the nevirapine treatment. Conclusions. We demonstrated that genetic variations in CCHCR1 are strongly associated with nevirapine-induced rash. A predictive model that includes genetic and clinical risk factors for nevirapine-associated rash might be useful in lowering the incidence of rash associated with nevirapine initiation among HIV-infected patients.