Dictionary > Tandem repeat

Tandem repeat

Definition
noun, plural: tandem repeats
(molecular biology) A type of repeated sequence in which the copies are repeated one after another along a chromosome
Supplement
The repeated sequences occur as multiple copies of nucleic acids in the genome. These repeats may involve the DNA or the RNA. There are three major types of repeated sequences: (1) terminal repeats, (2) tandem repeats, and (3) interspersed repeats.
Tandem repeats are repeated nucleotide sequences in which the copies lie adjacent to each other. It may be repetition(s) of one or more nucleotides. For example, CG CG CG CG CG is a tandem repeat wherein the sequence CG is repeated five times.
Tandem repeats include satellite DNAs, microsatellites, and minisatellites. Satellite DNA is a tandem repeat wherein the DNA copies are chiefly non-coding. It is present mainly in the centromere and heterochromatin. A microsatellite is a small tandem repeat ranging in length from 1-6 or more base pairs, repeated typically five to fifty times. A minisatellite is also a small tandem repeat but with relatively longer base pairs, i.e. from 10 to 60 base pairs, repeated typically five to fifty times.
Examples of tandem repeats are the 40S rRNA genes in somatic cells of toads, of which there are about 500 copies.
See also:


You will also like...

Geological Periods
Geological Periods

Geological periods is a study guide that cites the different geological periods on Earth's timeline. Each has a brief ov..

Psychiatry and mental disorders
Psychiatry & Mental Disorders

Different mental disorders are described here. Read this tutorial to get an overview of schizophrenia, affective mood di..

Pink Lotus plant on a pond
Freshwater Lentic Communities & Animals

This tutorial looks at some of the communities in freshwater lentic habitats. For instance, symbiosis occurs in a commun..

Biological Cell Defense
Biological Cell Defense

Organisms employ different strategies to boost its defenses against antigens. Humans have an immune system to combat pat..

Structural depiction of catalase, an enzyme
Protein Activity and Cellular Metabolism

Proteins have a crucial role in various biological activities. Get to know how proteins are able to perform as enzymes, ..

Chromosome Mutations
Chromosome Mutations

Mutations can also influence the phenotype of an organism. This tutorial looks at the effects of chromosomal mutations, ..

Related Articles...

No related articles found

See all Related Topics