Welcome to the  Urea Cycle Disorder and the Propionic Acidemia International Patient Registries. The Registries provide a way for UCD and PA patients and families worldwide to improve the understanding of the disorders and accelerate research by reporting information about how the disorder affects them.  The Registry is itself an IRB-approved research project and the data collected will help characterize the condition of people living with UCD or PA. Please select the registry for your diagnosis for more information and to begin the process: