About 3% or so of the human genome has highly repetitive sequences or simple-sequence DNA or simple sequence repeats or satellite DNA or microsatellites which are less than 10 bp long short sequences, repeated in multiples per cell. Satellite DNA, also termed as microsatellite, show relative uniformity within species and great variability between closely related species. Also, different individuals differ in a number of repeats of sDNA. This DNA polymorphism is used in DNA fingerprinting to create DNA profiles of individuals.
The length of satellite regions are highly variable between people. These form small peaks during density gradient centrifugation and thus are invaluable for identification purposes.