Tau pathology is also common in LRRK2-PD cases, ranging from 79% to 100% [11, 12], similar to the incidence of tau pathology in idiopathic PD, leading to the hypothesis that LRRK2 mutations could predispose patients to the accumulation of either α-synuclein or tau pathology. The gene discussed is LRRK2; the disease is Parkinson disease.