PSI Representation

Overview

Shows different representations of the PSI values for a set of PCR reactions. This tool provides a means for visualizing the changes in PSI values for a primer pair across different samples. Provides heatmap, spreadsheet and histogram representations.

Background

Tool developed to visualize changes in Alternative Splicing Events (ASEs) over several samples.

Interpretation

Heatmap

The PSI data is represented in a matrix where rows are the primer pairs used and columns are the assay samples. Each matrix square is color-coded in a rainbow color range from dark red to dark blue that is proportional to the PSI value (see example below). A grayscale color range is used to troubleshoot the PSI calculation:

Light gray

Neither the short nor the long amplicons are detected.

Dark gray

PSI calculation was filtered out because of low molarity (sum of long and short molarities below 5 nM).

White

Cannot select short/long amplicon (either fewer than 2 expected peaks or only one candidate with more than two expected peaks)

Black

This assay was not performed.

Spreadsheet

The PSI data matrix can be viewed in a spreadsheet file (MS Excel format). Look for the 'Data file' title to get the hyperlink.

Histogram

The PSI data is represented in several histograms, one for each primer pair, that show the distribution of PSI values across the samples. The histogram is viewable on the primer pair analysis page.

Contacts

• Philippe Thibault

Credits

Julien Gervais-Bird

Implemented the PERL-Graphic Library

Kevin Koh

Implementation of the heatmap representation.

Philippe Thibault

Implementation of the analysis.