Taken together, these data show the reduction of the key calcium regulatory proteins PLD1, iPLA2 and synaptotagmin-1 in GBA-N370S iPSC-dopamine neurons suggest a possible link between mitochondrial calcium dysregulation, reduced mitochondrial function, and impaired neurophysiological activity which may ultimately contribute to the preferential vulnerability of dopamine neurons in PD. The gene discussed is PLD1; the disease is Parkinson disease.