Consistent with this, inclusion‐containing neurons in both humans55 and hTyr‐overexpressing rodents43 often exhibit TH downregulation, which reflects neuronal dysfunction at early stages of neurodegeneration.8 In addition, similar to hTyr‐overexpressing rodents, the number of neuronal inclusions in PD brains at advanced stages of the disease is much lower than that observed in cases involving early PD.16 Here, TH is linked to Parkinson disease.