Research into the field of skin biology has grown exponentially over the past two decades. Even though the fundamental molecular pathways are still not fully understood, there have been significant advances in our understanding of the underlying mechanisms involved in the pathogenesis of genodermatosis. The cloning of many candidate genes involved in the etiology of skin diseases has been facilitated by initial cytogenetic evidence. This review will synthesize recent findings that led to the discovery of candidate-genes for anhidrotic ectodermal dysplasia, Williams-Beuren syndrome, neurofibromatosis-I and tricho-rhino-phalangeal syndrome. © Blackwell Munksgaard, 2004.