The ‘hypermethylator’ phenotype of SDHx-mutated tumours is a product of succinate-dependent inhibition of the TET family of DNA demethylases (Killian et al. 2013; Kiss et al. 2008; Letouze et al. 2013; Xiao et al. 2012), hence is not observed in VHL-mutated disease. The gene discussed is VHL; the disease is neoplasm.