Astrocytes are the most abundant cells in the CNS and change to a reactive phenotype (so-called reactive astrogliosis) that is characterized by enhanced glial fibrillary acidic protein (GFAP) expression and cellular hypertrophy (Sofroniew 2009; Pekny and Pekna 2014; Rossi 2015) in response to ischaemic stroke. This evidence concerns the gene GFAP and ischemic stroke.