LRRK2 and Parkinson disease: Previous findings suggest differences seen in LRRK2 mutation carriers are a result of early-onset disease or are due to enrichment of unique Ashkenazi-specific genetics rather than pathogenic events specific to LRRK2. Studies done in a variety of different mutation carrier groups have controlled for these differences (early-onset disease, Ashkenazi Jewish PD, and even non-PD mutation carriers) providing further evidence that these differences are central to LRRK2 dysregulation11,18–20.