Induced Pluripotent Stem Cell (Ipsc) technology enables the generation and study of living brain tissue relevant to Parkinson's disease (PD) ex vivo. Utilizing cell lines from PD patients presents a powerful discovery system that links cellular phenotypes observed in vitro with real clinical data. Differentiating patient-derived iPSCs towards a dopaminergic (DA) neural fate revealed that these cells exhibit molecular and functional properties of DA neurons in vitro that are observed to significantly degenerate in the substantia nigra of PD patients. Clinical symptoms that drive the generation of other relevant cell types may also yield novel PD-specific phenotypes in vitro that have the potential to lead to new therapeutic avenues for patients with PD. Due to their early onset and non-familial origin, differentiated nervous tissue from these patients offer a key opportunity to discover neuron subtype-specific pathological mechanisms and importantly interrogate the contribution of their genetic background in susceptibility to PD.