Savage et al. in their literature review advanced the absence of a link between the severity of psoriasis (PASI) and the likelihood of developing PsA.6 That was confirmed in later studies.16,33,43 Wilson et al. contrari-wise, showed that severe psoriasis were a predictive factor of developing PsA.44 Actually, it has been shown that synovium and skin lesions in PsA express the proinflammatory cytokine tumor necrosis factor α (TNFα); therefore, the larger affected skin area of psoriasis may result in increased systemic levels of TNFα and therefore in developing PsA.45,46. The gene discussed is TNF; the disease is psoriasis.