Researchers "have collaborated on a project to restore neuron function to parts of the brain damaged by Huntington's disease (HD) by successfully transplanting HD-induced pluripotent stem cells into animal models. ... Induced pluripotent stem cells (iPSCs) can be genetically engineered from human somatic cells such as skin, and can be used to model numerous human diseases. They may also serve as sources of transplantable cells that can be used in novel cell therapies. In the latter case, the patient provides a sample of his or her own skin to the laboratory. In the current study, experimental animals with damage to a deep brain structure called the striatum (an experimental model of HD) exhibited significant behavioral recovery after receiving transplanted iPS cells. The researchers hope that this approach eventually could be tested in patients for the treatment of HD. ... the transplanted cells will be genetically identical to the patient and therefore no medications that dampen the immune system to prevent graft rejection will be needed. ... transplanted iPSCs initially formed neurons producing GABA, the chief inhibitory neurotransmitter in the mammalian central nervous system, which plays a critical role in regulating neuronal excitability and acts at inhibitory synapses in the brain. GABAergic neurons, located in the striatum, are the cell type most susceptible to degeneration in HD."