Individuals with Urea Cycle Disorders (UCD) cannot remove ammonia, a waste product, from the blood. The purpose of this study is to conduct a longitudinal investigation of the natural history, morbidity, and mortality in people with UCD. This study will look at how people with a UCD grow and deve...

Mitochondrial diseases are caused by dysfunction of the mitochondria, which are specialized compartments that are present in every cell of the body except red blood cells. Mitochondria generate more than 90% of the energy that the body needs to sustain life and support growth. When they fail, les...