Genetic control of psoriasis is relatively distinct from that of metabolic syndrome and coronary artery disease

Psoriasis is a common chronic inflammatory skin disease, associated with significant comorbidity, for example, metabolic syndrome (MetS) and coronary heart disease (CHD). This association implies that the risk to develop these diseases is commonly controlled or that the presence of one disease favours manifestation of the other. Therefore, we assessed the catalogue of genome-wide association studies (GWAS) to analyse whether psoriasis, MetS and CHD share susceptibility loci. Interestingly, genetic control of psoriasis is almost completely independent from both MetS and CHD. In contrast, MetS and CHD share 10 common loci. Like by GWAS analysis, psoriasis susceptibility genes showed close clustering in Ingenuity Pathway Analysis, while genes conferring susceptibility to MetS and CHD were interlinked separately. These findings lead to the hypothesis that the clinically observed co-occurrence of psoriasis with MetS and CHD may be due to a common environmental factor, for example, diet, which is known as a risk factor for all of these diseases.