SpectralTAD

SpectralTAD identifies hierarchical topologically associated domains (TADs) from Hi-C contact matrices to characterize multi-level chromatin organization.

Key Features:

• Hierarchical detection: Detects primary TADs and nested sub-TADs to represent multi-level chromatin organization.
• Sliding window spectral clustering: Implements a sliding window-based, modified spectral clustering framework that uses gaps between consecutive eigenvectors to delineate TAD boundaries.
• Automatic parameter selection: Selects parameters algorithmically without requiring manual tuning.
• Robustness to data variability: Maintains performance across variations in sequencing depth, resolution, and Hi-C data sparsity.
• Output format: Produces BED files containing coordinates of detected TADs for downstream genomic analyses.
• Performance validation: Has been tested against four state-of-the-art TAD callers and identifies domains enriched with classical boundary marks and conserved across biological contexts.

Scientific Applications:

• 3D genome architecture analysis: Characterizes hierarchical TAD structures to inform studies of chromatin organization.
• Gene regulation studies: Enables investigation of how TADs influence gene expression and cellular function.
• Comparative genomics: Facilitates detection of conserved TAD boundaries across cell lines and tissues for comparative analyses.

Methodology:

SpectralTAD applies a sliding window spectral clustering approach to Hi-C contact matrices and identifies domain boundaries by detecting gaps between consecutive eigenvectors, yielding hierarchical TAD calls.