Darier's disease is an uncommon skin disorder with autosomal dominant transmission. During the course of the investigation of a large family in which several members are affected with schizophrenia, it was found that many family members also suffer from Darier's disease. Recent advances in molecular genetic techniques have made the identification of such families important for an understanding of the causes of inherited diseases. The role of genetic linkage analysis of Darier's disease is discussed following a review of the current state of knowledge of its pathogenesis and genetics. CLINICAL BACKGROUNDDarier's disease is a potentially disfiguring disease characterized by the presence of warty, brown papules and plaques primarily affecting the so-called seborrheic areas of the skin on the face, scalp, trunk, and groin (Fig. 1).1 In addition, involvement of nails and mucous membranes is common.2 In more severe cases, the lesions may become extensive, vegetative, and malodorous leading to major adverse social consequences for the sufferer. Affected persons are at risk for widespread cutaneous viral and bacterial superinfection, which can lead to further disability and hospitalization.The disease typically has its onset in the second decade of life and tends to persist lifelong with periods of exacerbation related to sweating, minor cutaneous trauma, and ultraviolet light exposure. Complete remissions are rare.Routine histopathology of Darier's disease shows characteristic abnormalities with evidence of abnormal keratinization and acantholysis (loss of cohesion) of epidermal cells.4Treatment remains unsatisfactory although the use of oral aromatic retinoids (isotretinoin and etretinate) has benefitted some patients with more severe disease.5 More definitive therapy awaits better understanding of the pathogenesis of the disease.