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Sequence Tags

Tag Description

Expressed Sequence Tags)

Short (usually about 300-500 bp), single-pass sequence reads from mRNA (cDNA). Typically they are produced in large batches. They represent a snapshot of genes expressed in a given tissue and/or at a given developmental stage. They are tags (some coding, others not) of expression for a given cDNA library.

(Genome Survey Sequences)

Contains sequences that are genomic in origin rather than cDNA (mRNA). Contents include (but are not limited to) these data types:

  • Random "single pass read" genome survey sequences.
  • Single pass reads from cosmid/BAC/YAC ends (these could be chromosome specific, but need not be)
  • Exon trapped genomic sequences
  • alu PCR sequences

(High Throughput Genomic Sequences)

"Unfinished" DNA sequences that are generated by high-throughput sequencing projects.

(Sequence Tagged Sites)

Short (about 200-500 bp) sequences that are operationally unique in a genome (i.e., can be specifically detected by PCR in the presence of all other genomic sequences), and that define a specific position on the physical map. STSs can therefore be used to generate mapping reagents that map to single positions within the genome.


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