Use of PCR for Mapping STS and EST or TST - Most of the molecular markers (RFLPs and RAPDs) in a variety of plant materials are now also being converted into sequence tagged sites (STS, where genomic DNA is involved) and expressed sequence tags or transcribed sequence tags (EST or TST, where cDNA probes are used).
This has already been done in materials like rice and Arabidopsis and will be extended to other materials in future. These STS or EST maps will be useful, because each marker will be identified by a known sequence and not by a DNA or cDNA clone of unknown constitution