Network-based analysis of multivariate gene expression data

Wei Zhi1, Jane Minturn, Eric Rappaport

  • 1Department of Biostatistics and Epidemiology, New Jersey Institute of Technology, Newark, NJ, USA.

Insights

This study introduces a new empirical Bayes method using Markov random fields to analyze gene expression data, improving the identification of differentially expressed genes and pathways. The approach enhances sensitivity in detecting biological signals in complex genomic datasets.

Area of Science:

  • Genomics
  • Bioinformatics
  • Systems Biology

Background:

  • Multivariate gene expression data are crucial for understanding genomic responses under ordered conditions.
  • Identifying genes with differential expression patterns over time or dosage is key to uncovering biological processes.
  • Existing empirical Bayes methods often assume gene independence, limiting their effectiveness.

Purpose of the Study:

  • To develop an alternative empirical Bayes approach for multivariate gene expression data analysis.
  • To model gene dependencies using a discrete Markov random field (MRF) prior.
  • To improve the identification of differentially expressed genes and perturbed pathways.

Main Methods:

  • Introduced a novel empirical Bayes approach incorporating a discrete Markov random field (MRF) prior.
  • Modeled dependencies between differential expression patterns of genes within biological networks.
  • Utilized simulation studies and a real-world microarray time course dataset.

Main Results:

  • The proposed MRF-based method effectively identifies differentially expressed genes and subnetworks.
  • Demonstrated higher sensitivity compared to methods that ignore pathway information.
  • Achieved similar false discovery rates to existing procedures.

Conclusions:

  • The MRF prior approach offers a powerful tool for analyzing multivariate gene expression data by leveraging gene network dependencies.
  • The method successfully identified key genes and subnetworks in MAPK, focal adhesion, and prion disease pathways.
  • These findings provide insights into cell differentiation mechanisms in neuroblastoma cell lines.