Abstract
Multi-organ research investigates interconnections among multiple human organ systems, enhancing our understanding of human aging and disease mechanisms. Here we use multi-organ imaging, individual- and summary-level genetics, and proteomics data consolidated via the MULTI Consortium to delineate a brain-heart-eye axis using brain patterns of structural covariance (PSCs), heart imaging-derived phenotypes (IDPs) and eye IDPs. We find that proteome-wide associations of the PSCs and IDPs show within-organ specificity and cross-organ interconnections. Pleiotropic effects of common single-nucleotide polymorphisms are observed across multiple organs, and key genetic parameters are estimated for single-nucleotide polymorphism-based heritability, polygenicity and selection signatures across the three organs. A gene-drug-disease network shows the potential of drug repurposing for cross-organ diseases. Co-localization and causal analyses reveal cross-organ causal relationships between PSC/IDP and chronic diseases, such as Alzheimer's disease, heart failure and glaucoma. Finally, integrating multi-organ/omics features improves prediction for systemic disease categories and cognition compared with single-organ/omics features, providing future avenues for modelling human aging and disease.