The latter group consists of a) drug induced hypertrichosis, in particular anti-convulsants such as phenytoin and other drugs, including corticosteroids, cyclosporine and interferon alpha 2; b) malnutrition and anorexia nervosa; c) endocrine disorders, juvenile dermatomyositis and infectious diseases; d) metabolic diseases such as mucopolysaccharidoses (Hurler, Hunter, Sanfilippo syndromes), congenital porphyrias, and adrenal enzymatic deficiency; e) ovarian and adrenal neoplasms [6]. Here, IFNA2 is linked to cutaneous porphyria.