mosaicism

Condition of being mosaic (2).

- cellular m. a chimerism in which a tissue contains cells from different zygotes; e.g., in humans, involving erythrocytes.

- chromosome m. mosaic (2).

- gene m. mosaic (2).

- germinal m., gonadal m. a state in which some of the germ cells of the gonad are of a form not present in either parent, because of mutation in an intermediate progenitor of these cells.

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mo·sa·i·cism mō-'zā-ə-.siz-əm n the condition of possessing cells of two or more different genetic constitutions

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n.

a condition in which the cells of an individual do not all contain identical chromosomes; there may be two or more genetically different populations of cells. Often one of the cell populations is normal and the other carries a chromosome defect such as Down's syndrome or Turner's syndrome. In affected individuals the chromosome defect is usually not fully expressed.

• mosaic adj.

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mo·sa·i·cism (mo-zaґĭ-siz″əm) in genetics, the presence in an individual of two or more cell lines that are karyotypically or genotypically distinct and are derived from a single zygote. Cf. chimerism.