[18F]MPPF binding is observed mainly in brain regions with a high density of 5-HT1A receptors such as hippocampus and raphe nuclei [5–7] and it has been used to explore various psychiatric and neurologic diseases such as epilepsy [8], narcolepsy [9], Alzheimer’s disease [10], or multiple system atrophy [11]. This evidence concerns the gene HTR1A and early-onset autosomal dominant Alzheimer disease.