Background: Genome-wide association studies in white and Chinese Han populations have found that the single-nucleotide polymorphism (SNP) rs610604, at the tumour necrosis factor (TNF)-α-induced protein 3 (TNFAIP3) locus, is associated with psoriasis, and is also associated with response to TNF blockade in psoriasis.
Aim: To examine whether this SNP is also associated with the clinical traits of psoriasis vulgaris (PV).
Methods: A hospital-based case-control study was performed, which involved 647 subjects [351 patients with PV and 296 healthy controls (HC)]. The rs610604 variants were typed using a SNaPshot assay.
Results: Both the G allele and the dominant model genotype (GG + GT) of rs610604 were associated with risk of PV (OR = 1.53; P = 0.01 and OR = 1.68, P < 0.01, respectively). In genotype-phenotype analysis, both the G allele and the GG + GT genotype were also associated with the clinical severity of PV. Severe cases [Psoriasis Area and Severity Index (PASI) > 6] had a higher frequency of the G allele and the GG + GT genotype compared with mild cases (PASI ≤ 6) (OR = 2.03, P = 0.001 and OR = 2.46, P < 0.001, respectively). In addition, rs610604 was significantly associated with almost all of the phenotypes in subphenotype-control analyses.
Conclusions: SNP rs610604 in the TNFAIP3 locus is associated with the clinical severity of PV in a Chinese Han population.
© 2014 British Association of Dermatologists.