Multi-omics biomarkers as emerging determinants in precision disease diagnosis and therapeutic monitoring

Biomarkers objectively measurable biological characteristics indicating normal physiology, pathological states, or pharmacological responses are indispensable to precision medicine. The convergence of multi-omics platforms encompassing genomics, epigenomics, transcriptomics, proteomics, metabolomics, and lipidomics has fundamentally transformed biomarker discovery by enabling cross-platform data integration that no single omics approach can achieve alone. Horizontal integration within individual omics layers, and vertical integration across multiple omics dimensions, enable identification of molecular signatures with greater diagnostic precision and therapeutic predictability. This review critically evaluates: biomarker classification and clinical utility; disease-specific monitoring and predictive applications; contemporary analytical and biosensing strategies; a comparative analysis of nanotechnology-based detection platforms with explicit assessment of detection limits, scalability, and Technology Readiness Levels (TRL); regulatory pathways governing biomarker qualification including the FDA Biomarker Qualification Programme, the BEST framework, and EMA qualification opinions; bioinformatics and radiomic tools; and emerging technologies including spatial transcriptomics, CRISPR-based diagnostics, and AI-driven liquid biopsy. Each biomarker and detection platform is contextualised against its evidence level and TRL to prevent conflation of preclinical observations with clinically validated markers.