POLR2C and psoriasis: Although its expression pattern in psoriatic skin differs from healthy skin [7, 8] and its overexpression influences cell proliferation [6, 9, 10], its role as a putative psoriasis effector gene has remained unsettled, partially because it has been suggested to function in several divergent biological processes such as the regulation of steroidogenesis via mitochondrial steroidogenic activator protein (STAR) [8, 11] or muscle differentiation via RNA polymerase II subunit 3 (RPB3) [12].