Integrating the results from all the individual regions of the brain showed that although some ipsilateral regions were more affected by USP19 KO than their contralateral counterparts (SNc, Str, and PAG) (Supplementary Fig. 2c), an overall significant reduction in pSyn pathology was found in KO ipsi- and contralateral regions compared to the counterpart regions in WT animals (Fig. 2c), suggesting a less efficient progression of the PD-like pathology in the brains of USP19 KO animals than in WT brains. This evidence concerns the gene USP19 and Parkinson disease.