Regarding the molecules related to inflammatory processes (C-reactive protein,interleukin 6 or IL-6, soluble receptor of tumor necrosis factor alpha or TNF-alpha)oxidative stress (isoprostane), neurotrophic factors (brain derived neurotrophicfactor or BDNF) among others, the value of these as reliable biomarkers of AD is notyet clear. This evidence concerns the gene IL6 and Alzheimer disease.