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Updated: Jul 14, 2025

Analyzing Multifactorial RNA-Seq Experiments with DiCoExpress
Published on: July 29, 2022
Adjustment of spurious correlations in co-expression measurements from RNA-Sequencing data.
Ping-Han Hsieh1,2, Camila Miranda Lopes-Ramos3,4,5, Manuela Zucknick6
1Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo 0318, Norway.
Quantile normalization methods can create false gene co-expression links. We developed SNAIL (Smooth-quantile Normalization Adaptation for the Inference of co-expression Links) to accurately identify gene networks from RNA-Sequencing data.
Area of Science:
- Computational Biology
- Bioinformatics
- Genomics
Background:
- Gene co-expression analysis identifies coordinated gene expression patterns.
- RNA-Sequencing data normalization is crucial for accurate analysis.
- Certain normalization methods, like quantile-based ones, can introduce false associations.
Purpose of the Study:
- To develop a normalization method that avoids false-positive associations in gene co-expression analysis.
- To improve the accuracy of co-expression network inference from RNA-Sequencing data.
- To address limitations of existing normalization techniques in handling large-scale heterogeneous data.
Main Methods:
- Developed SNAIL (Smooth-quantile Normalization Adaptation for the Inference of co-expression Links), a novel normalization method.
- SNAIL is based on smooth quantile normalization, specifically designed for co-expression inference.
- Evaluated SNAIL's performance in avoiding false-positive associations in co-expression and network analyses.
Main Results:
- SNAIL effectively prevents the formation of false-positive associations in co-expression measurements.
- The method supports downstream network analyses without introducing spurious links.
- SNAIL allows for the retention of associations involving genes with low expression in specific sample subgroups, avoiding arbitrary filtering.
Conclusions:
- SNAIL is a robust normalization method for gene co-expression analysis using RNA-Sequencing data.
- The method enhances the reliability of co-expression network construction.
- SNAIL has significant potential for advancing network modeling and association-based approaches in large-scale biological data analysis.
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