Activated Syk then signals via PI3K/AKT, JNK, and phospholipase-C γ2 (PLCG2, variants of which associate with AD risk) to promote cell survival, proliferation and phagocytosis (Arndt et al., 2004; Sims et al., 2017; Tsai et al., 2020; Ennerfelt et al., 2022). This evidence concerns the gene SYK and Alzheimer disease.