Cytochrome b is a validated targetin Plasmodium, with atovaquone being a Pf cytochrome b inhibitor used in combination withproguanil in one ofthe most commonly prescribed medications for malaria prophylaxis.A wider use of atovaquone in antimalarial formulations is hamperedby the rapid rise of parasite resistance,28,29 which can be at least in part due to the high frequency of mutationsin the mitochondrial genome, leading to a high prevalence of resistantparasites in the population. The gene discussed is MT-CYB; the disease is malaria.