Skin types in dysplastic nevus syndrome.

In order to determine if individuals with dysplastic nevi (DN) are relatively more sun-sensitive than controls who do not have DN, the sun-reactivity skin types (based on the Harvard classification) were determined in these two groups. Compared with controls, sun-sensitive types were significantly overrepresented in the DN group. This is consistent with the hypothesis that the fundamental defect in the dysplastic nevus syndrome is the genetically unstable melanocyte, which is susceptible to neoplastic transformation induced by sunlight.