LRRK2 and Parkinson disease: For example, the frequency of the prevalent p.G2019S mutation in the leucine-rich repeat kinase 2 (LRRK2) gene accounts for up to 40% of PD cases in North African Arab-Berbers and Ashkenazi Jews but is found in less than 0.1% of Asian PD patients [14], suggesting that Asian patients with PD may have different gut microbiota than Western PD patients.