KNG1 (kininogen 1) encodes a multifunctional plasma protein that serves as a precursor for the potent vasoactive peptide bradykinin and functions as a cysteine protease inhibitor. The protein plays crucial roles in the kallikrein-kinin system, where it contributes to coagulation regulation and vascular homeostasis 1. KNG1 mutations are associated with hereditary angioedema with normal C1 inhibitor (HAEnCI), a rare autosomal dominant disorder characterized by recurrent episodes of potentially life-threatening angioedema 23. Beyond its role in angioedema, KNG1 variants significantly influence circulating adiponectin levels, linking it to metabolic disorders including obesity and type 2 diabetes 4. The protein shows altered expression patterns in various pathological conditions: it serves as a potential biomarker for hepatocellular carcinoma when detected in small extracellular vesicles 5, exhibits structural changes in cerebrospinal fluid during aging 6, and demonstrates causal associations with venous thromboembolism risk through Mendelian randomization studies 7. Additionally, KNG1 interacts with PAI-1 in endometrial stromal cells, contributing to decidualization processes important for embryo implantation 8. These diverse functions highlight KNG1's importance in vascular biology, inflammation, metabolism, and reproductive health.