Corticospinal motor neurons are affected in motor neuron diseases and damaged in spinal cord injuries. In this grant application, we proposed to induce human embryonic stem cells to generate corticospinal motor neurons. In this past grant period, we have generated neurons that express the corticospinal motor neuron genes. We are currently characterizing the cell types of theses neurons in detail. In the near future we will transplant them into the brains in mice to test whether they can form functional neural circuits.