Although, HLA-DRB1*07 occurred significantly more frequently in PsA cases than controls, we have previously reported that this allele exhibits considerable LD with HLA-Cw*06 (correlation (r2) = 0.46).34 Therefore, it was not unexpected that, after adjusting for the presence of HLA-Cw*06 phenotype, the association of HLA-DRB1*07 with PsA as a whole group (OR 1.38, 95% CI 0.88, 2.17, p = 0.16) or in the subgroup with type I psoriasis compared with controls (OR 1.63, 95% CI 0.96, 2.78, p = 0.07) was no longer statistically significant. Here, HLA-DRB1 is linked to psoriasis.