LRRK2 and Parkinson disease: Future studies should aim for comprehensive genetic and genomic screening, longer follow-up periods, expanded sample sizes for rarer (e.g., double-variant) subgroups, incorporation of technology-based tools such as sensors and advanced analytics that can enhance “deep phenotyping” of patients94,95, and biomarker studies10,51,68, to better delineate the impact of LRRK2 variants on PD genetic epidemiology, phenotype, and biology.