BDNF production was increased in aMCI; these results are is in line with data showing higher BDNF serum levels in preclinical stages of Alzheimer’s disease (Laske et al., 2006; Angelucci et al., 2010) and with post-mortem examinations of AD brains indicating a significant increase of BDNF concentration in hippocampus and parietal cortex (Durany et al., 2000) and of its receptor TrkB in astrocytes and senile plaques (Connor et al., 1997). Here, NTRK2 is linked to early-onset autosomal dominant Alzheimer disease.