Indeed, Pink1-KO mice, a model that is typically asymptomatic of PD and void of dopaminergic degeneration, exhibited a pronounced reduction in the density of tyrosine hydroxylase-positive neurons in the dorsal and ventral striatum and dopamine transporters following infection by a pathogenic Gram-negative bacterium, Citrobacter rodentium (Matheoud et al., 2019). The gene discussed is TH; the disease is Parkinson disease.