Since PD is an α-synucleinopathy, α-synuclein is associated with motor symptom7, 8 and several non-motor symptoms, such as cognitive impairment9, fatigue10, apathy11 and rapid eyes movement (REM) sleep behavior disorder (RBD)12, etc. In addition to α-synuclein, other pathological proteins, such as β amyloid (Aβ) and tau pathology were increasingly reported to be associated with a part of non-motor symptoms of PD. The gene discussed is MAPT; the disease is Parkinson disease.