The overarching goal of this work is to utilize stem cell based models of Parkinson’s disease (PD) derived from cells of PD affected patients that harbor mutations in the LRRK2 gene so that we may elucidate the deleterious role of mutated LRRK2 in disease. Mutations in LRRK2 are the most common cause of familial PD. The disease presentation for these patients with LRRK2 mutation is typically clinically similar to those with sporadic disease, making the onset of disease due to LRRK2 dysfunction clinically relevant. We have utilized stem cells harboring a mutation in LRRK2 and also daughter cells of that line in which genomic editing techniques have been applied to correct the PD mutation or disrupt the LRRK2 gene. We have generated the same kind of cells in culture that are lost during PD and hope that next, we can determine how these mutations that eventually cause disease disrupt normal neuronal function. We have made great progress in the understanding the expression of LRRK2 in early differentiation of stem cells to neurons and his will inform our future studies on mutation caused dysfunctions.