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What DNA fingerprinting does

A DNA fingerprint looks like a series of strips like a barcode. It is actually a 'snapshot' of a particular sequence of letters - base pairs - of DNA, which is scattered throughout your chromosomes. This 'phrase' of DNA base pairs is repeated several times at each chromosomal location - a sort of 'genetic stammer'. The exact number of repeats varies from person to person, giving DNA sequences of different lengths. You have your own combination of DNA phrases of different lengths, inherited from your parents.

The first DNA fingerprint.
The first DNA fingerprint.
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