In Alzheimer’s disease, there is an increase in the number of Dock2-expressing microglia, a finding of pathogenic significance given that Dock2 deficiency reduces the size of β-amyloid (Aβ) plaque in cerebral cortex and hippocampus of a mouse model of AD (Cimino et al., 2009, 2013). Here, DOCK2 is linked to early-onset autosomal dominant Alzheimer disease.