Alterations in the function and signalling pathways and polymorphisms in Toll-like receptor 2 (TLR2) have been associated with the development of AD (Potaczek et al., 2011; Yu et al., 2015) whilst Killer immunoglobulin-like receptor (KIR), specifically KIR2DS1, seems to be associated with protection from AD (Niepiekło-Miniewska et al., 2013). Here, TLR2 is linked to Alzheimer disease.