For regulation of neuronal growth, Bmp4 is a ligand of bone morphogenetic receptors (can activate Acvr1), whereby its increased expression correlates to decreased hippocampal cell proliferation during AD (Li et al., 2008) and white matter destruction following chronic hypoperfusion of the brain (Uemura et al., 2018). Here, ACVR1 is linked to Alzheimer disease.