Given that Mtk has no known targets outside of its role in combating fungal infection, we considered the possibility that effects of the MtkR1 mutation following TBI result from effects on expression of other components of the Toll and Imd pathways rather than effects of loss of Mtk molecular activity (De Gregorio 2002; Moghaddam et al. 2017). This evidence concerns the gene TLR4 and fungal infectious disease.