Given the role of DKK1 in synaptic changes and in AD (Caricasole et al., 2004; Marzo et al., 2016; Purro et al., 2012), we next investigated whether modulation of DKK3 levels affected Dkk1 mRNA levels in the hippocampus of WT and J20 mice injected with Scr or Dkk3 shRNA. The gene discussed is DKK1; the disease is Alzheimer disease.