Moreover, elevated concentrations of IL-15 and IL-6, lower eGDR value, and higher HOMAIR index found in the first-degree relatives with positive anti-islet antibodies suggest that serum IL-15 and IL-6 levels might be used as a biomarkers of AD risk and that insulin resistance could also play a role in the prediabetic stage. This evidence concerns the gene IL15 and Alzheimer disease.