Rett syndrome is genetic disorder that leads to loss of acquired spoken language and hand skills, and gait abnormalities by age 3. It specifically affects girls because the mutation is located on one of their X chromosomes in the MECP2 gene. Rett syndrome is difficult to study in humans because it is not ethically possible to obtain nerve cells from these individuals. One renewable source of nerve cells from patients is a new technology called induced Pluripotent Stem (iPS) cells. IPS cells are generated from a patient skin biopsy and these stem cells can then produce limitless amounts of nerve cells from that patient. These cells can be studied and therapies tested without putting the patient at any risk. The process of stem cell induction from skin is called reprogramming and is performed by delivering a combination of four genes that normally control the stem cell state. To study Rett syndrome, we made iPS cells from Rett syndrome patient skin cells. Our goal now is to use these iPS cells to make nerve cells with the disease to identify abnormalities in nerve function in comparison to the healthy controls. We will also use the Rett syndrome nerve cells to test for candidate drugs that can reverse the abnormal nerve functions. Overall, this new source of nerve cells will be useful to understand the mechanism of disease that causes Rett syndrome, and to screen for drugs in human nerve cells to treat the disease in the future.