Namely, research focused on astrocyte reactivity in neuronal disorders, which primarily consisted of immunostaining assays for the expression of glial fibrillary acidic protein (GFAP), an ubiquitously used marker in mammalian models, mounted enough evidence for the exploitation of astrocytes as potential biomarkers for traumatic brain injury (TBI), brain tumors, and stroke, as well as a wide range of neurodegenerative diseases [30,31,32]. The gene discussed is GFAP; the disease is neurodegenerative disease.