Glutarate is also an endogenous metabolite that participates in diverse physiological processes.[7] Deficiency in mitochondrial glutaryl‐CoA dehydrogenase (GcdH) may block glutarate catabolism and induce an inherited metabolic disorder called glutaric aciduria.[8, 9, 10] Glutarate also plays significant roles in immune processes involving T cell regulation.[11, 12] It can directly regulate T cell metabolism through glutarylation of the E2 subunit of the pyruvate dehydrogenase complex, and modulate T cell anti‐tumor function through inhibiting.[11]. Here, GCDH is linked to glutaric aciduria.