Retraction: The Journal of Neuroscience has received a report describing an investigation by the Shanghai Institute of Biological Sciences, Chinese Academy of Sciences, which found major data misrepresentation in the article “Lmx1b-Controlled Isthmic Organizer Is Essential for Development of Midbrain Dopaminergic Neurons” by Chao Guo, Hai-Yan Qiu, Ming Shi, Ying Huang, Randy L. Johnson, Marcelo Rubinstein, Sheng-Di Chen, and Yu-Qiang Ding, which appeared on pages 14097–14106 of the December 24, 2008 issue. Because the results cannot be considered reliable, The Journal is retracting the paper.