TREM2 and Alzheimer disease: Among these genes were those well known to be associated with synaptic activities such as Homer1 and Arc, glial activation such as Ccl6, C1q, and Gfap, and genetic AD risks involving glial changes such as Apoe and Trem2. Inflammatory changes shown by Tnfa and Cox1 and Cox2 and glial activation shown by Iba1 and Cd11b by quantitative polymerase chain reaction (qPCR) further supported the gene expression profiling of cortical samples (fig.