KIR2DL1 and Encephalopathy: Except for KIR2DS4+, KIR2DS3+, and the inhibitor gene KIR2DL1+, which were found to be increased in patients with encephalopathy, it was found that the frequency of most KIR genes (activators and inhibitors) decreased in patients with encephalopathy who died from MF (Figure 2A).