Among the gene pairs with a compensatory relationship, and a known synthetic lethality, PDS5A/PDS5B appears especially promising as a therapeutic target—there is evidence of synthetic lethality both in a large scale analysis of diverse cell lines (De Kegel et al, 2021) and in a combinatorial screen (Parrish et al, 2021), and PDS5B is recurrently deleted in patient tumours. The gene discussed is PDS5B; the disease is neoplasm.