SLC44A2 is a mitochondrial and plasma membrane-localized transmembrane protein with diverse roles in cardiovascular and hematologic homeostasis. Despite its name suggesting choline transporter activity, SLC44A2 does not function as a classical choline transporter. Instead, it regulates vascular smooth muscle cell (VSMC) phenotypic switching through interaction with NRP1 and ITGB3, activating TGF-β/SMAD signaling to maintain contractile gene expression and suppress aortic aneurysm development 1. In heart failure, SLC44A2 participates in the Von Willebrand factor-mediated regulation of neutrophil extracellular trap formation, which drives mitochondrial dysfunction in cardiomyocytes 2. SLC44A2 carries the CTL2 blood group antigen and the Csa/Csb red blood cell antigens, with a non-synonymous polymorphism (rs2288904) associated with venous thromboembolism risk 34. Complete SLC44A2 deficiency causes progressive hearing impairment, recurrent arterial aneurysms, and epilepsy in affected individuals 5. In colorectal cancer, SLC44A2 functions as a tumor suppressor by inhibiting mitochondrial fatty acid oxidation through promotion of MUL1-mediated CPT2 degradation 6. These findings establish SLC44A2 as a pleiotropic regulator linking vascular biology, hemostasis, and metabolic homeostasis with therapeutic implications for multiple diseases.