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Chromatin

Definition(s)

The material of chromosomes. It is a complex of DNA; histones; and nonhistone proteins (chromosomal proteins, non-histone) found within the nucleus of a cell.

Definition from: MeSH via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

The genetic material of the nucleus, consisting of deoxyribonucleoprotein, which occurs in two forms during the phase between mitotic divisions: 1) as heterochromatin, seen as condensed, readily stainable clumps; 2) as euchromatin, dispersed lightly staining or nonstaining material. During mitotic division the chromatin condenses into chromosomes.

Definition from: NCI Thesaurus via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

Chromatin is a substance within a chromosome consisting of DNA and protein. The DNA carries the cell's genetic instructions. The major proteins in chromatin are histones, which help package the DNA in a compact form that fits in the cell nucleus. Changes in chromatin structure are associated with DNA replication and gene expression.

Definition from: Talking Glossary of Genetic TermsThis link leads to a site outside Genetics Home Reference. from the National Human Genome Research Institute

See also Understanding Medical Terminology.

 
Published: December 22, 2014