INPP5D and Alzheimer disease: Studies by Tsai and colleagues [23] revealed significantly elevated INPP5D expression in human AD microglial cells, and demonstrated a direct correlation between increased INPP5D expression and amyloid deposition in specific brain regions, including the inferior frontal, parahippocampal and superior temporal gyri, as well as in the frontal pole, although they did not delve into mechanisms driving specific INPP5D gene expression.