Definition
noun, plural: interspersed repeats
A type of repeated sequence in which the copies are dispersed throughout the genome and not side by side
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.
Interspersed repeats are repeated sequence wherein the copies are interspersed, i.e. dispersed throughout the genome. This makes it different from the tandem repeats wherein the copies lie side by side. In the interspersed repeats, the copies are nonadjacent.
Interspersed repeats are present in all the genomes of the eukaryotes. Transposable elements (transposons), such as DNA transposons and retrotransposons, are interspersed repeats.
One possible importance of interspersed repeats is to allow new genes to evolve by uncoupling the gene conversion network. For instance, the Alu elements are specialized for uncoupling intrachromosomal gene. Another example is the long interspersed nuclear elements (LINEs) specialized for uncoupling interchromosomal gene conversion. These repeats are therefore essential in promoting evolution and the development of new species.
See also:
- repeated sequence
- transposable element
- DNA transposon
- retrotransposon
- Alu element
- long interspersed nuclear element
