disease has major feature Hyperammonemia urea cycle disorder urea cycle disorder or inherited hyperammonemia https://github.com/monarch-initiative/mondo/issues/4985 https://github.com/monarch-initiative/mondo/issues/5378 GARD:0026463 A disorder of amino acid metabolism that has its basis in the disruption of the urea cycle or an inherited hyperammonemia (any specific disease which causes an inherited increased concentration of ammonia in the blood). MONDO:0800153