Redefining Parkinson's disease research using induced pluripotent stem cells.

Parkinson's disease (PD) is a movement disorder associated with the degeneration of nigral dopaminergic (DA) neurons. One of the greatest obstacles for PD research is the lack of patient-specific nigral DA neurons for mechanistic studies and drug discovery. The advent of induced pluripotent stem cells (iPSCs) has overcome this seemingly intractable problem and changed PD research in many profound ways. In this review, we discuss recent development in the generation and analyses of patient-specific iPSC-derived midbrain DA neurons. Results from this novel platform of human cellular models of PD have offered a tantalizing glimpse of the promising future of PD research. With the development of the latest genomic modification technologies, dopaminergic neuron differentiation methodologies, and cell transplantation studies, PD research is poised to enter a new phase that utilizes the human model system to identify the unique vulnerabilities of human nigral DA neurons and disease-modifying therapies based on such mechanistic studies.