Tandem repeat sequences

This is a term from genetics, which describes a pattern that helps determine an individual's inherited traits.Tandem repeats and variable number tandem repeats in DNA occur when a pattern of two or more nucleotides is repeated and the repetitions are directly adjacent to each other. An example would be:ATTCGATTCGATTCG in which the sequence ATTCG is repeated three times.Tandem repeats can be very useful in determining parentage.  Short tandem repeats are used for certain genealogical DNA tests.
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Multiple copies of the same DNA base sequence on a chromosome; used as a marker in physical mapping of the chromosome.