What does mosaicism mean?
Mosaicism most commonly denotes a condition in which a single organism contains two or more genetically distinct populations of cells. The differences usually arise when a genetic mutation occurs after an early developmental stage, causing the mutation to be present in only some cells rather than throughout the body. Consequently, genetic tests may find the alteration in one tissue but not another. The word can also refer, more unusually, to the art or technique of making mosaics. In medical and biological writing, mosaicism is a specialized term associated with genetics, embryology, oncology, and genetic testing. Its broader implication is variation within an apparently unified whole: although every cell originated from the same organism, later changes can produce a cellular patchwork. For that reason, mosaicism is especially important in the diagnosis and interpretation of inherited and developmental conditions.
nounIn genetics and medicine, mosaicism is the condition of having two or more genetically distinct populations of cells within an organism. In a less common artistic sense, it refers to the technique or art of making mosaics.
- The presence within one organism of two or more genetically distinct cell populations, usually arising from a mutation after fertilization.
- The technique or art of making mosaics from small pieces of material.
"Genetic testing revealed mosaicism in the patient's affected tissue."
"The laboratory confirmed tissue-specific mosaicism in the biopsy."
"The museum conservator studied the mosaicism of the Roman floor before restoring it."
Usually used as an uncountable noun; the plural is rare and chiefly appropriate when referring to distinct cases or types of mosaicism.
"Researchers compared several forms of mosaicism found in the cohort."
Mosaicism means your cells are not always genetically identical: you may carry distinct cellular populations, like a biological patchwork.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does mosaicism come from?
Mosaicism was formed in English by adding the suffix "-ism" to the earlier word "mosaic." In its artistic sense, "mosaic" comes through Late and Medieval Latin from Greek roots associated with the Muses; the same broader Greek family includes words such as "muse," "museum," and "music." The biological sense developed by applying the idea of a mosaic—a design composed of varied parts—to the mixture of genetically distinct cells within an organism.
Related word forms
How mosaicism is actually used
In medicine and genetics, the term is technical and usually appears in phrases such as "genetic mosaicism" or "chromosomal mosaicism." The artistic sense is relatively uncommon; "mosaic" or "mosaic art" is more natural in general discussion.
Easily confused with mosaicism
A mosaic is an artwork or decorative design formed from small pieces; mosaicism is more commonly the genetic condition in which distinct cell populations occur within one organism.