Hyperammonemia type 2.

Most common area cycle disorder,has OTC deficiency.

X- linked and partially Dominant.

Has Orotic aciduria: accumulated carbamoyl phosphate reaches cytoplasm and enters Pyrimidine synthesis,Orotic acid is an intermediate which accumulates.
Orotate precipitates in Urine as pink coloured Gravel/Stones.

Elevated Glutamine and Alanine, low levels of citrulline and Arginine.