GFAP correlated with executive functions (r = − 0.37, p = 0.01) overall, while GFAP correlated with processing speed (r = − 0.68, p < 0.001) and NFL with verbal episodic memory (r = − 0.43, p = 0.02) among subjects with a CSF AD profile. This evidence concerns the gene GFAP and Alzheimer disease.