Proteome-Wide Mendelian Randomization Identifies Candidate Causal Proteins for Cardiovascular Diseases

Integration of human genomics and other omics across different ancestries provides novel, affordable, and systematic approach for target identification. We used Mendelian randomization approaches to unravel causal associations between 2,940 circulating proteins and 19 CVD. We found 218 proteins that impacted risk of one or more CVDs through forward MR (106 and 182 using cis-pQTLs only and cis- + trans-pQTLs, respectively), among which 107 were previously reported as associated with CVD or CVD-related traits. There were 102 proteins replicated (FDR < 5%, 53 with cis-pQTLs only and 88 with cis- + trans-pQTLs) using the FinnGen Olink data. BTN3A2 was highlighted as a novel candidate gene for ischemic stroke, suggesting a crosstalk between immune modulation and stroke pathogenesis. Single cell integration prioritized PAM for stable angina pectoris and ventricular arrhythmia and LPL for peripheral artery disease, whose transcriptional expressions were enriched in cardiomyocytes. Forward and reverse MR found largely non-overlapping proteins (only 2 overlapped: LGALS4 and MMP12), suggesting distinct proteomic causes and consequences of CVD. Our study provides human genetics-based evidence of novel candidate genes, a foundational step towards full-scale causal human biology-based drug discovery for CVD.