Mosaic

mosaic /mo·sa·ic/ (mo-za´ik)

1. a pattern made of numerous small pieces fitted together.

2. in genetics, an individual or cell cultures having two or more cell lines that are karyotypically or genotypically distinct but are derived from a single zygote.

3. in embryology, the condition in the fertilized eggs of some species whereby the cells of early stages have developed cytoplasm which determines the parts that are to develop.

4. in plant pathology, a viral disease characterized by mottling of the foliage.

---

mo·sa·ic (m-zk)

adj.

Patterned in small squares; tesselated.

n.

An organism exhibiting mosaicism.

---

Mosaic

A term referring to a genetic situation, in which an individual's cells do not have the exact same composition of chromosomes. In Down syndrome, this may mean that some of the individual's cells have a normal 46 chromosomes, while other cells have an abnormal 47 chromosomes.

Mentioned in: Down Syndrome, Turner Syndrome

---

mosaic

a pattern made of numerous small pieces fitted together; in genetics, the occurrence in an animal of two or more cell populations, each having a different chromosome complement, e.g. XY/XXY mosaic.

---

mosaic animals

all the genotypes arise from a single zygotic genotype because of chromosomal loss or mitotic nondisjunction.

ecological mosaic

a pattern of interspersed ecosystems of similar size and on a recurring basis.