These absolute contraindications include pyruvate carboxylase (PC) deficiency; disorders of fatty acid beta-oxidation (i.e. primary carnitine deficiency or PCD), carnitine palmitoyltransferase deficiency, carnitine-acylcarnitine translocase (CACT) deficiency, 3-hydroxyacyl-coenzyme A dehydrogenase (HADH) deficiency, medium-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (MHADD), long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency, medium-chain acyl-CoA dehydrogenase deficiency (MCADD), very-long-chain acyl-CoA dehydrogenase deficiency (VLCADD); and porphyria. This evidence concerns the gene SLC25A20 and pyruvate carboxylase deficiency disease.