To our knowledge, only a few studies have evaluated the combination of GFAP with other biomarkers so far and presented the utility of plasma GFAP not just in discriminating healthy controls from patients with AD but also in distinguishing Aβ+ from Aβ- individuals (Oeckl et al., 2019; Asken et al., 2020; Verberk et al., 2020). This evidence concerns the gene GFAP and Alzheimer disease.