GBA1 and Parkinson disease: There is reason to hope that therapies targeting Parkinson’s disease with specific associated genetic variants, such as GBA1 or LRRK2 variants, might demonstrate disease modification in a subset of people with Parkinson’s disease.17 Our findings show that there are many previously unidentified people with Parkinson’s disease who could qualify for precision medicine trials, especially ones focused on GBA1 (approaching 10% of all participants) and, to a lesser extent, LRRK2.