Details of the different types of satellite DNA
| Satellite | Minisatellite (telomeric) | Minisatellite (hypervariable) | Microsatellite | |
|---|---|---|---|---|
| Other names | – | – | Variable number tandem repeats (VNTRs) | Short tandem repeats (STRs) |
| Size of repeat unit | 5 to several hundred bases | Mainly “TTAGGG”' in humans | 6 to > 50 bp | 1 to 5 bp |
| Total expansion size | 100 kb to several Mb | 10–15 kb | 100 bp to ∼ 20 kb | 10 to ∼100 bp (excluding certain trinucleotide repeats) |
| Location | Heterochromatin, especially centromeric heterochromatin | All telomeres | Throughout genome, but most clustered in telomeric regions | Distributed almost ubiquitously throughout genome |
| Biological functions | Unknown (probably none) | Protects chromosome ends, provides means of terminal sequence replication, possible roles in chromosome pairing and cell ageing | Very rare examples of expression, importance unknown. Otherwise unknown (probably none) | Unknown, but may fine tune gene expression. Again trinucleotides are special case. (Contingency genes in prokaryotes) |