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​Tandem Repeat
Definition
A tandem repeat is a sequence of two or more DNA bases that is repeated numerous times in a head-to-tail manner on a chromosome. Tandem repeats are generally present in non-coding DNA. In some cases, tandem repeats can serve as genetic markers to track inheritance in families. They can also be useful for DNA fingerprinting in forensic studies.
![Tandem-repeat](/sites/default/files/media/images/tg/Tandem-repeat.jpg)
Narration
Tandem Repeats. Tandem repeats are interesting because they're recognizable repeats in the genome. They vary in the sequence that is repeated and how many times they are repeated in a given genome. One reason that makes them fascinating to study is that, depending on where they are in the genome, they can cause something as serious as Huntington's disease — which is a rare disease that causes the nerve cells in the brain to break down. They are also useful independent of health and disease status of a person, such as when they are used in forensic profiling to identify missing persons.
![Lucia Hindorff, Ph.D., M.P.H.](/sites/default/files/media/images/hindorff.png)
Lead Extramural Training Program Director
Training, Diversity and Health Equity Office