In addition, a recent review discusses the controversial results around the role of BDNF polymorphism in vulnerability to stroke (Kotlêga et al., 2017) and the role of BDNF polymorphism in AD is a matter of debate (Lim et al., 2016; Rogaeva and Schmitt-Ulms, 2016). This evidence concerns the gene BDNF and Alzheimer disease.