Page tree

Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Every sequence in IGB is identified by its genome version and chromosome names, which must therefore be distinct.

Tracks

...

Annotations, Graphs, Sequences, Reads and Alignments

Tracks: Tracks are rows of data that appear in the IGB interface. When you open a file, the data within the file will appear in one or more tracks. Older versions of IGB refered to tracks as "tiers" and so you may see this term used elsewhere in the User's guide.

Annotations

Annotations indicate the known or suspected locations of genomic features such as genes, exons, promoter regions, pseudogenes, and so forth. Annotations may consist of a single coordinate, a single span with a start and end positions, or a collection of spans. Most annotations reside on either the plus or minus strand of a chromosome, but some do not.

...

  • single-coordinate feature*: splice sites
  • single-span feature, with strand*: an exon
  • single-span feature, no strand*: a restriction site
  • multi-span feature, with strand*: a gene model

Graphs

Graphs consists of numeric data associated with single or multi-base positions in a chromosome. Some file formats for graphs include wig,

Sequences are sets of DNA residues comprising a chromosome. Sequences can be fully or partially loaded from local files, QuickLoad sites, or DAS servers. IGB allows you to examine sequence data in a separate window called the Sequence Viewer.

Alignments

Alignments represent how sequences obtained from an experiment (such as reads from an RNA-Seq experiment) align onto the reference genomic sequence. At low zoom they look like annotations, but with marks representing mismatches between the read and the reference genome whenever these data are available. At higher zoom, the aligned sequence bases become visible. File formats for alignments include BAM and PSLX.

Probe set alignments

Probe set alignments consists of a target sequence aligned onto a chromosome and the location of probes relative to the aligned target sequence. This data type is Affymetrix-specific.