A recent observation in keeping with this hypothesis is that the relatively weakly inhibitory combination of KIR2DL3 and C1 is a risk factor for cerebral malaria, and the activating combination of KIR2DS1 and C2 may be a risk factor for non-cerebral severe malaria (Hirayasu et al. 2012). This evidence concerns the gene KIR2DL3 and cerebral malaria.