Expression of the astrocyte marker glial fibrillary acidic protein (GFAP) increases with age in humans and mice (Kimbroughet al., 2015; Kovacs et al., 2018; Kress et al., 2014; Stichel & Luebbert, 2007; Wruck & Adjaye, 2020; Zhuang et al., 2019), plays an important role in astrogliosis (Faulkner et al., 2004; Lundkvist et al., 2004; McLean & Lane, 1995; Nawashiro et al., 1998; Pekny & Pekna, 2004; Sofroniew & Vinters, 2010), and its increased expression is correlated with Alzheimer's disease (AD) (Wruck et al., 2016). The gene discussed is GFAP; the disease is Alzheimer disease.