Sequence-tagged site

A sequence-tagged site (or STS) is a short (200 to 500 base pair) DNA sequence that occurs but once in a genome and whose location and base sequence are known.

STSs can be detected by the polymerase chain reaction (PCR), and are useful for localizing and orienting the mapping and sequence data reported from many different laboratories. They also serve as landmarks on the developing physical map of a genome.STS is making genomics easier. They are used in shotgun sequencing.

Expressed sequence tags (ESTs) are STSs derived from cDNAs.