Glutaric aciduria type 1 (GA1) is an autosomal recessive disorder due to a deficiency of glutaryl-CoA dehydrogenase (GCDH), a mitochondrial matrix protein involved in the catabolism of tryptophan, lysine, and hydroxylysine (61). The gene discussed is GCDH; the disease is glutaryl-CoA dehydrogenase deficiency.