[Pigmentary mosaicism: a literature review]

Pigmentary mosaicism (PM) refers to various developmental patterns of skin pigmentation. It can present as a hypopigmented, hyperpigmented, or mixed form combining both types (cutis tricolor). In about one-third of cases, PM is associated with extracutaneous manifestations, most often neurological. The cause of PM is primarily genetic, including chromosomal mosaicism, mosaic intragenic pathogenic variants, as well as epigenetic mosaicism in females carrying a pathogenic variant on the X chromosome. This article summarizes recent literature in order to better identify the underlying causes and improve the management of these patients.