Glutaric aciduria type 1 (GA1) develops due to mutations in glutaryl-CoA dehydrogenase (GCDH) (Fig. 1), which results in severe neurologic defects [6], while glutaric aciduria type 2 (GA2) is caused by mutation of genes involved in electron transfer in the mitochondrial respiratory chain [7]. The gene discussed is GCDH; the disease is glutaric aciduria.