However, the population risk of known mutations and risk loci only represents a fraction of the known detectable heritable component of disease, suggesting that additional genetic influence is yet to be identified.1, 2 Most genes associated with PD have been discovered through linkage mapping studies in large family studies, such as SNCA3 and LRRK2. 4, 5, 6 Some studies contain large sequencing cohort validation analyses such as the one nominating VPS13C. 7The majority of the recent studies that nominate potential PD genes lack replication of results. The gene discussed is LRRK2; the disease is Parkinson disease.