OmiXAI: An Ensemble XAI Pipeline for Interpretable Deep Learning in Omics Data
1. OmiXAI is a novel ensemble explainable AI (XAI) pipeline designed for deep learning models applied to multi-omics data, enabling feature attribution that is both biologically meaningful and computationally scalable.
2. The framework integrates six model-aware gradient-based interpretation methods—Integrated Gradients, InputXGradients, Guided Backpropagation, Deconvolution, Saliency Maps, and GNNExplainer—applied to both CNN and GNN models.
3. OmiXAI was benchmarked on Z-DNA prediction using a dataset with 1,950 omics features and achieved high classification performance (ROC-AUC up to 0.98), while identifying a minimal set of just 50 highly predictive features without loss in accuracy.
4. The pipeline’s strength lies in its hybrid ranking approach: it combines relevance scores across methods to prioritize features, mitigating the inconsistencies often seen in standalone XAI outputs.
5. Two custom deep learning models were trained: ConvMZC (CNN) and GraphMZC (GNN). ConvMZC achieved an F1-score of 0.88, while GraphMZC reached 0.81—demonstrating the complementary value of both architectures.
6. OmiXAI is generalizable and supports interpretation of both nucleotide-based and omics features. It was also successfully adapted for k-mer-based feature analysis, identifying motifs consistent with Z-DNA structural signatures.
7. The study emphasizes that many gradient-based XAI methods—though efficient—can be noisy or biased. OmiXAI alleviates this through consensus scoring, providing more robust and interpretable results.
8. Compared to permutation feature importance (PFI) used in earlier work, OmiXAI provided more stable and biologically aligned rankings, identifying key histone marks, transcription factors, and RNA polymerase binding as top features.
9. Feature reduction experiments showed that reducing the feature set from 1,950 to 50 maintained predictive performance, highlighting the pipeline’s utility in omics-based feature engineering and dimensionality reduction.
10. Designed with modularity in mind, OmiXAI can be easily extended to other biological tasks and architectures, including transformers, by computing gradients with respect to either input features or attention weights.
💻Code:
github.com/aameliig/OmiXAI
📜Paper:
biorxiv.org/content/10.1101/…
#XAI #ExplainableAI #Omics #DeepLearning #Bioinformatics #FeatureImportance #NeuralNetworks #Genomics #ComputationalBiology #AI4Science