Although there was no overall significant correlation to disease type or severity in terms of PASI score, elevated IFN-γ serum concentration has been associated with active psoriasis in multiple studies (Jacob et al., 2003; Arican et al., 2005; Moustafa et al., 2009; Takahashi et al., 2010; Kurtovic and Halilovic, 2018). This evidence concerns the gene IFNG and psoriasis.