A new multi-omics study has revealed genomic alterations that underlie phaeochromocytomas and paragangliomas. The analysis showed that the genetic status of these tumours is strongly correlated with multi-omics data (for example, methylation patterns and microRNA expression profiles). Tumour subtypes can therefore be defined on the basis of a set of genomic alterations. The researchers suggest that omics-based tests will be developed in the future that will enable precise molecular classification of these tumours, paving the way to personalized medicine.