DIAPH1 and Alzheimer disease: It was recently shown that DIAPH1 is upregulated in the brains of AD vs. age-matched control human subjects; that its expression co-localizes with that of RAGE; and that the AD-specific upregulation of DIAPH1 was localized to microglia (132), the endogenous/resident yolk sac-derived immune/inflammatory cells of the brain.