SLC30A5 encodes ZnT5, a zinc transporter that maintains cellular zinc homeostasis by facilitating zinc efflux from the cytoplasm 1. The protein functions as a zinc ion:proton antiporter and exists as multiple splice variants with distinct subcellular localizations - either in the Golgi apparatus or at the plasma membrane including the apical enterocyte membrane 23. ZnT5 plays a critical role in dietary zinc absorption in the small intestine, where its expression is homeostically regulated by zinc availability through both transcriptional repression and mRNA stabilization mechanisms 23. The gene contains a CpG island in its promoter region that can be regulated by DNA methylation 4. Biallelic loss-of-function variants in SLC30A5 cause severe human disease phenotypes including perinatal lethal cardiomyopathy with hydrops fetalis 5 and severe neonatal hypotonia syndrome with respiratory failure leading to death in infancy 1. These pathogenic variants result in reduced cytosolic zinc concentrations, demonstrating the essential role of ZnT5 in maintaining proper cellular zinc homeostasis 1. The transporter is also differentially expressed in prostate cancer, suggesting broader roles in disease pathogenesis 6.