In order to test for selective DA neuron loss as seen in PD brains, we exposed 7 dpf Tg(isl1[ss]: Gal4-VP16,UAS: eGFP)zf154 larvae expressing GFP in Rohon-Beard neurons to 250 nM CPF and found no differences compared to controls at 7 dpf (Fig. 6D). This evidence concerns the gene ISL1 and Parkinson disease.