Related Experiment Video
Updated: May 13, 2026

08:00
Analyzing Tumor Gene Expression Factors with the CorExplorer Web Portal
Published on: October 11, 2019
SVAw - a web-based application tool for automated surrogate variable analysis of gene expression studies
Mehdi Pirooznia1, Fayaz Seifuddin, Fernando S Goes
1Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine, Baltimore, MD, USA. pzandi@jhsph.edu.
Source Code for Biology and Medicine
|March 19, 2013
Summary
Surrogate variable analysis (SVA) identifies and corrects for unknown factors in gene expression data. A new web application, SVAw, offers a user-friendly interface for automated SVA, improving biological accuracy and reproducibility in high-throughput studies.
Area of Science:
- Genomics
- Bioinformatics
- Computational Biology
Background:
- Gene expression studies often contain heterogeneity from unmeasured technical, genetic, environmental, or demographic factors.
- Failure to account for these sources of variation can obscure biological insights and reduce reproducibility.
- Surrogate variable analysis (SVA) is a method to identify and correct for such hidden factors.
Purpose of the Study:
- To develop a user-friendly web application for performing SVA on genome-wide expression data.
- To automate the SVA workflow and provide comprehensive analysis results.
- To enhance the accuracy and reproducibility of gene expression studies.
Main Methods:
- Development of SVAw, a web application based on the open-source Bioconductor SVA package.
- Implementation of a fully automated and user-friendly analysis workflow.
- Calculation of probe/gene statistics pre- and post-SVA, with regression analysis results.
- Generation of a comprehensive report with graphical comparisons.
Main Results:
- SVAw provides a user-friendly interface for SVA of genome-wide expression studies.
- The application automates the analysis workflow and calculates relevant statistics.
- Results include pre- and post-SVA regression analyses and graphical comparisons.
Conclusions:
- SVAw is a freely accessible web server for surrogate variable analysis of high-throughput datasets.
- It effectively removes unwanted and unknown sources of variation in gene expression data.
- The tool enhances biological accuracy and reproducibility in genomic studies.
