LRRK2 and Parkinson disease: Globally, genetic variability within LRRK2 confers the highest genotype- and population-attributable risk for PD [1], and the frequency of many variants appears to be population-specific; LRRK2 p.R1441G/C is most frequent in European Basques [1] and Belgians [2]/Italians [3], respectively, p.G2385R [4] and p.R1628P [5] are found in East Asians, and p.G2019S is common in Ashkenazi Jews [6] and North African Arab-Berbers [7].