AIF1 and autism: In contrast, the expression of microglial markers TREM2, DAP12, CX3CR1, and AIF1 were lower in autism tissue than in control tissue, with fold changes of 0.780 (P = 0.0056), 0.797 (P = 0.0083), 0.659 (P = 0.0029), and 0.808 (P = 0.0052), respectively.