Psoriasis is an erythematous, scaly chronic inflammatory dermatosis and occurs due to altered epidermal differentiation and hyperproliferation due to faulty signals that speed up the growth cycle of skin cells. Psoriasis reduces quality of life, and psoriatic patients generally have higher risk for metabolic disease. Psoriasis is associated with many burdening comorbidities, which often share similar pathogenic features and follow a progressive pattern. Genetic variation in human genome causes specific kind of disease, and nowadays, research is focused on metabolic pathways that trigger psoriasis and related comorbidities. In addition, genetic variations are also important for psoriasis treatment regime and response. The purpose of this section is to shown to genetic epidemiology, pharmacogenetics, immune genetics of psoriasis and related comorbidities.