Branzoli et al. found that magnetic resonance spectroscopy is able to detect accumulation of cystathionine in 1p/19q co-deleted gliomas in vivo, which is related to the lower expression of both PHGDH and CTH compared with their non-co-deleted counterparts, leading to perturbed serine- and cystathionine-metabolism9. Here, CTH is linked to central nervous system cancer.