Delaney and colleagues used ganciclovir to inhibit cell division of GFAP-positive cells in neonatal GFAP-HSV-TK mice, and demonstrated that astrocyte reduction in newborn pups results in ataxia, neuronal excitotoxicity and a disorganization of Purkinje cells and radial glia [135]. The gene discussed is GFAP; the disease is cerebellar ataxia.