Regression and disappearance of clinical symptoms in some cases of genodermatoses.

Genetic skin diseases are usually thought of as stable phenotypes caused by a mutant gene. However, a review of the literature on genodermatoses and my personal experience with a number of these disorders show that the concept of a stable phenotype is not always true. A number of genodermatoses actually show a regression of symptoms. Among these are monilethrix, several types of erythrokeratoderma, several forms of palmoplantar keratoderma such as the varians Wachters type and the Richner-Hanhart syndrome, and some forms of epidermolysis bullosa, for example the Dowling-Meara type. Three different reasons possibly underlying the regression of symptoms in genetic diseases are briefly discussed: (1) environmental factors, (2) hormonal influences and (3) movable, transposable elements causing instability of the genome.