Urine organic acid analysis revealed that MCAD−/− mice developed an organic acid profile similar to MCAD-deficient human patients. Specifically, when fasted for 18 h, MCAD−/− mice developed significantly elevated concentrations of adipic, suberic, and sebacic acids and hexanoylglycine as compared to MCAD+/+ controls, which showed trace to no detectable amounts of the same organic acids (Table 1). Adipic acid is not specific to MCAD deficiency. We also evaluated β-hydroxybutyric and acetoacetic concentrations and found no significant differences between MCAD genotypes (data not shown).