Propionic acidemia is a common organic acidemia, caused by deficiency of propionyl-CoA carboxylase (PCC), which catalyzes the carboxylation of propionyl-CoA to D-methylmalonyl-CoA. PCC is a dodecameric enzyme of alpha-PCC and beta-PCC subunits, nuclearly encoded by genes PCCA and PCCB, respectively. Mutation in either gene cause propionic acidemia