Hence, it is possible that HCP5-C carriers mount a strong immune reaction to viral infection, and when psoriasis is associated with other genes such as corneodesmosin, POU5F1, MICA, and HLA-C in the MHC and genes outside the MHC in genetically susceptible individuals [116], then this reaction might lead to excessive inflammation in skin and joints. This evidence concerns the gene HLA-C and viral infectious disease.