TREM2 and Alzheimer disease: Furthermore, using cell sorting with RNA sequencing and lipidomics, it has recently been suggested that a loss of function in the gene encoding for TREM2 (triggering receptor expressed on myeloid cells 2), which is selectively expressed in microglia and like ApoE, has been linked to late onset of AD and causes neuronal damage and the accumulation of cholesterol esters in the Trem2−/− mouse brain and in isolated Trem2−/− microglia.