SLC14A2 encodes multiple isoforms of the UT-A urea transporter family, which are essential for urea transport across cellular membranes in the kidney 1. The gene spans approximately 300 kb on chromosome 18 and contains 24 exons that produce six different UT-A isoforms through alternative splicing driven by two distinct promoters 2. The primary function involves mediating urea flux across the inner medullary collecting duct, which is critical for the kidney's urine concentrating mechanism 3. UT-A1 and UT-A3 are localized to the inner medullary collecting duct, while UT-A2 is found in the thin descending limb 2. These transporters are acutely regulated by vasopressin through phosphorylation and membrane trafficking, with long-term regulation involving changes in protein abundance in response to hydration status and hormonal signals 3. The human UT-A1 protein shows 89% identity to rat UT-A1 and functions as a phloretin-inhibitable urea transporter when expressed in heterologous systems 4. Clinically, SLC14A2 mutations are associated with hypertension and metabolic syndrome due to its essential role in maintaining urea homeostasis 5. Knockout studies demonstrate that loss of UT-A function results in urine concentrating defects 6.