Short DNA Sequence Repeats


The human genome contains numerous segments of short, reiterated nucleotide sequences that are often located near or within transcriptional units. Despite extensive characterization of these DNA elements over three decades, no sequence‐specific role has been firmly established. However, it has been recognized that expansions of certain trinucleotide repeat sequences are associated with several inherited human disorders.

Keywords: DNA; human genetics; microsatellites; trinucleotide repeats; DNA repair

Figure 1.

Tetraplex structure. The tetraplex consists of four strands of DNA arranged in a parallel array as indicated by the direction of the arrows. Four guanine (G) bases from each strand lie in a single plane and are stabilized by hydrogen bonds to each adjoining base. The central portion of the guanine quartet is occupied by a monovalent cation.



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Further Reading

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Mitas, Michael(Apr 2001) Short DNA Sequence Repeats. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0000574]