Specifically, one of the MAM functions that is increased in AD is the synthesis of PtdSer by phosphatidylserine synthases 1 and 2 (PTDSS1/2) (Vance, 2014; Kannan et al, 2017 #2382, Wu & Voelker, 2004; Area‐Gomez et al, 2012 #234), resulting in higher levels of this phospholipid in MAM and other membranes in AD cells and tissues. The gene discussed is PTDSS1; the disease is Alzheimer disease.