define the specific contributions of glia to the neuropathology and clinical phenotype of HD. Similarly, our understanding and therapeutic modeling of disorders such as amyotrophic lateral sclerosis (ALS), already reported to derive in part from astrocytic pathology (Di Giorgio et al. 2007; Meyer et al. 2014; Yamanaka et al. 2008), may be substantially refined by comparing the in vivo phenotypes of mice engrafted with hGPCs generated from patients with different ALS-associated mutations.
