Genetic mosaicism is the presence of an acquired somatic mutation in a clonal subset of cells that differs from the inherited germline genome. Genetic mosaicism is an attractive potential early biomarker for disease risk due to its established relationship
with aging, introduction of potentially deleterious mutations, and clonal selection and expansion of mutated cells. New genomic technologies and detection methods have detected higher than anticipated frequencies of clonal mosaicism in adult population studies,
stimulating investigation into the underlying contributors to development of genetic mosaicism as well as associated outcomes. Early studies have characterized the spectrum of detectable mosaic alterations and have begun to investigate whether detectable mosaicism
could be important as an overall biomarker for disease risk or in the case of hematologic cancers, identification of preleukemic clones.