crossmeta

crossmeta performs cross-platform and cross-species meta-analysis of high-throughput microarray gene expression data by automating retrieval, normalization, annotation, surrogate variable analysis (SVA), and differential expression analysis of raw GEO datasets from Affymetrix, Illumina, and Agilent platforms within the Bioconductor/R ecosystem.

Key Features:

• Cross-Platform Compatibility: Supports meta-analysis of microarray data from Affymetrix, Illumina, and Agilent platforms.
• Cross-Species Analysis: Enables comparative analyses across different organisms for cross-species studies.
• GEO Data Retrieval: Automates downloading of raw Gene Expression Omnibus (GEO) datasets.
• Data Normalization and Annotation: Performs normalization of raw GEO microarray data and applies annotations to probes and genes.
• Surrogate Variable Analysis (SVA): Incorporates surrogate variable analysis models to account for unmeasured sources of variation.
• Differential Expression Analysis: Facilitates identification of genes with significant expression changes between conditions or species.
• Bioconductor/R Integration: Operates within the Bioconductor framework using the R programming environment and Bioconductor package standards.

Scientific Applications:

• Comparative Genomics: Integrates cross-platform and cross-species expression data to compare gene expression patterns across organisms.
• Evolutionary Biology: Enables cross-species analyses that support evolutionary and functional genomics investigations.
• Systems Biology: Supports integrative analyses across datasets to study regulatory mechanisms and system-level gene expression responses.
• Differential Expression Studies: Identifies differentially expressed genes across conditions or species using normalized and SVA-corrected data.

Methodology:

Operates within Bioconductor/R; automates downloading of raw GEO datasets, performs normalization and annotation of microarray data, implements surrogate variable analysis models, and conducts differential expression analysis while leveraging Bioconductor package standards and testing.