Notably, the accumulation of 3-hydroxyglutarate and glutarate in the urine phenocopies the presentation of glutaric aciduria type I, an autosomal recessive disorder caused by a deficiency in glutaryl-CoA dehydrogenase (GCDH), which catalyzes the conversion of glutaryl-CoA to crotonyl-CoA (19–21). Here, GCDH is linked to glutaryl-CoA dehydrogenase deficiency.