Tech Briefs

ChromaBlast is a computer program that facilitates and accelerates processing and display of data by use of Microsoft Excel or other spreadsheet software that affords similar capabilities. The development of ChromaBlast was prompted by a need for improved means of analyzing and reviewing massive data sets produced in genomics and microarray-based gene-expression experiments. ChromaBlast is also generally applicable to other data sets that are amenable to spreadsheet representation.

Heretofore, analysis of such data has been facilitated by costly integrated software packages. Often, those packages offer no spreadsheet functionality and little or no other functionality for reduction or manipulation of data. As a result, a researcher must use spreadsheet software, then export the data to analysis software. After each run of the analysis software, the data must be reformatted or reduced in the spreadsheet. The process as described thus far must be repeated until the final set of data is appropriately formatted for the analysis package.

ChromaBlast is one component of a suite of software tools, called "BioTools.XLA," designed to enable the use of spreadsheet software to perform data reduction or basic analysis without having to manually switch back and forth between the spreadsheet software and the analysis software. ChromaBlast can be in stalled alone or as part of the suite. ChromaBlast normalizes columnar data, sorts the data into range bins selectable by the user, develops a color heat map from the data (see figure), and puts out the heat map and the bin assortment for review. By use of intrinsic tools in the spreadsheet software, output data can be filtered and sorted to emphasize data patterns and thereby facilitate rapid review of the data.

ChromaBlast is coded in Visual Basic for Applications (VBA) — a programming language designed to connect the macroinstruction programming functions of Excel with relatively sophisticated manual coding in a development environment. Preliminary macroinstructions (defined by keystrokes and program functions recorded during use of Excel) can be used to quickly construct a template for a specific piece of work. The macroinstruction record then serves as a conceptual framework for implementation of generalizations, functional options, and input from the user. Within VBA, it is also possible to add a multitude of functions that are not accessible in the macroinstruction-recording process. Thus, the programmer can quickly construct a template by use of macroinstructions, then add functionality and usability inside the VBA environment. VBA can also be used by itself to develop code from the beginning, as can any typical programming language.

This work was done by Barry N. Ford, Yimin Shei, and Stephen Bjarnason of Defence Research and Development Canada, and Catharine Richardson of Webgenii Consulting.

DRDC-0001

This Brief includes a Technical Support Package (TSP).

Tool for Processing and Displaying Genomics Data in Spreadsheets (reference DRDC-0001) is currently available for download from the TSP library.

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