IL12B, IL23A, IL23R and HLA-C*06 genetic variants in psoriasis susceptibility and response to treatment

The role of interleukin-23 is crucial in the pathogenesis of psoriasis, and IL23A, IL12B and IL23R genetic variants have been associated with the disease in genome-wide association studies. In the current paper we have conducted a confirmation study of the abovementioned genetic factors in a case-control analysis of 507 psoriatic patients and 396 controls from a Polish population, and subsequently analyzed the impact of genetic variants on response to topical and NB-UVB therapy in a subset of 306 patients. Case-control analysis revealed an association of IL12B rs3212227 and IL23R rs11209026 minor allele carrier status with reduced odds for psoriasis (OR = 0.66, 95%CI: 0.50-0.87, and OR = 0.41, 95%CI: 0.26-0.67, respectively), while HLA-C*06 allele carriers were more frequent in patients group (OR = 4.56, 95%CI: 3.41-6.10). The studied polymorphic variants of IL12B, IL23A, and IL23R genes did not influence therapy outcome, i.e. there were no significant differences in PASI reduction between patients with different genotypes. However, HLA-C*06 carriers showed poorer response to the applied treatment, when compared to non-carriers. The results of the current study confirm an association between IL12B and IL23R genetic polymorphism and psoriasis vulgaris (with a protective effect of minor alleles). HLA-C*06 carriers show reduced effectiveness of topical/NB-UVB therapy, and that observation could be potentially used in treatment personalization.