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Modern Genetic Analysis Chapter 13. Transposable Genetic Elements
Solved Problem

1. | Transposable elements have been referred to as "jumping genes" because they appear to jump from one position to another, leaving the old locus and appearing at a new locus. In light of what we now know concerning the mechanism of transposition, how appropriate is the term "jumping genes" for bacterial transposable elements? See answer

| Solution In bacteria, transposition occurs by two different modes. The conservative mode results in true jumping genes, because, in this case, the transposable element excises from its original position and inserts at a new position. A second mode is termed the replicative mode. In this pathway, transposable elements move to a new location by replicating into the target DNA, leaving behind a copy of the transposable element at the original site. When operating by the replicative mode, transposable elements are not really jumping genes, because a copy does remain at the original site. See question

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