A transposable element (TE), also transposon, or jumping gene, mobile genetic element, a nucleic acid sequence in DNA that can change its position within a genome, an observation first made via careful genetic studies in corn, by Barbara McClintock (leading to an eventual Nobel Prize in Physiology/Medicine in 1983).
TEs are very common in all types of organisms in nature, including in plants and animals. As of 2008, there were at least two classes of TEs: Class I TEs or retrotransposons, which generally function via reverse transcription; and Class II TEs or DNA transposons, which encode the protein transposase (and sometimes other proteins), which they require for insertion, excision, or other TE functions.
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