SELP encodes P-selectin, a calcium-dependent cell adhesion molecule that mediates critical interactions between activated endothelial cells, platelets, and leukocytes during inflammation and thrombosis 1. P-selectin binds to P-selectin glycoprotein ligand-1 (PSGL-1) on neutrophils and other leukocytes, facilitating leukocyte rolling and recruitment to sites of inflammation 1. The protein undergoes alternative splicing, with genetic variants like rs6128 affecting exon 14 skipping, which alters the ratio of transmembrane versus soluble P-selectin production 2. SELP genetic polymorphisms, particularly rs6136-T, are associated with increased disease risk in rheumatoid arthritis through enhanced gene expression 3. In sickle cell disease, P-selectin plays a crucial pathogenic role in vaso-occlusive crises, making it an important therapeutic target 4. The monoclonal antibody crizanlizumab, which blocks P-selectin interactions, has been approved to reduce vaso-occlusive crises in sickle cell disease patients 5. Additionally, SELP-positive tumor endothelial cells interact with CD8+ T cells through the ACKR1-CCL5 pathway, potentially enhancing radiotherapy response in cervical cancer 6. Platelet P-selectin expression shows high repeatability over time, suggesting strong genetic control of this adhesion molecule 2.