LRRK2 and Parkinson disease: Garrido et al. (2019) tested patients with idiopathic PD (IPD), LRRK2-PD, or LRRK2 non-manifesting carriers (NMCs). IPD was positive in 9 of 10 patients (sensitivity 90%), whereas RT-QuIC positivity for LRRK2-PD was found in 6 of 15 patients (40%) and LRRK-NMC was found in only 3 of 16 patients (18.8%) (Table 1).