Mosaicism in clinical genetics

Abstract

Genetic mosaicism is the state in which there are two or more different sets of cells in a single individual because of one or more postzygotic mutations, and its importance in clinical genetics has long been recognized (Hall, Am J Hum Genet 43: 355 [1988]). In this Perspective, a paper in this special issue on mosaicism from Cook et al. (Cold Spring Harb Mol Case Studies 7: a006125 [2021]) is discussed.