TREM2 and Alzheimer disease: Conversely, recent efforts in whole-exome and whole-genome sequencing of large AD case–control series unraveled three major genes—sortilin-related receptor (SORL1); triggering receptor expressed on myeloid cells-2 (TREM2); and ATP-binding cassette, sub-family A, member 7 (ABCA7)—the rare coding variants of which significantly increase the risk of AD with moderate to high OR [41].