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.

Toxoplasma gondii infection generally causes flu-like symptoms in healthy individuals; however, immunosuppression of the infected individual causes reactivation of the pathogen to its active form and relapse of the toxoplasmosis. Today it is known that toxoplasmosis triggers psychiatric disorders such as schizophrenia as well as behavioral changes such as suicide attempts. Although dermatological manifestations are very rare, the dermatological lesions are not unique. In addition, previous toxoplasma infection also causes congenital infections because of placental infection and causes birth defects and spontaneous abortion. T. gondii strains are mainly divided into three main clonal lineages, yet higher recombination rate causes unusual population structure and heterogeneous distribution of the pathogen. Both genetic variations, of the pathogen and the patients, are important for virulence property and success of the therapies. The scientist focuses on the genetic variations of the pathogens and individuals to achieve effective treatment and developed tailor-made medicines. Thus, understanding the molecular basis of the disease and the link of molecular mechanism with host immunity is important to fully know the disease and related disorders. In this chapter, we would like to evaluate the current knowledge on genetic, molecular characteristics of toxoplasmosis in view of public health genomics.