LRRK2 and Parkinson disease: To assess ASOs for their ability to induce exon 41 skipping in vitro, ASO 41-1 or 41-2 was transfected into LRRK2 G2019S PD patient-derived fibroblast cells and after 48 h RNA was collected and analyzed for LRRK2 exon 41 skipping by reverse transcriptase polymerase chain reaction (RT-PCR).