Study of Genetic Alzheimer's Disease Mutation Carriers in Preclinical Stages of the Disease 18F-Florbetaben Positron Emission Tomography Study

Inclusion Criteria: * Adult children (\> 18 yo) of genetic Alzheimer?s disease patients with a known mutation in PSEN1, APP o PSEN2 genes and who are either cognitively normal (CDR=0) or have mild symptoms of cognitive decline (CDR 0.5 or 1) * According to the principal investigator, participants must be committed to participate and complete all study procedures. * Has signed the Informed Consent Form voluntarily to participate in the study Exclusion Criteria: * Subjects that are not able to complete the study. * Any major disease or history of a major disease, especially hepatobilliar disease (AST /ALT ? 5 x ULN) or advanced renal insufficiency (creatinine ? 2 x ULN) * Current or previous history of alcohol abuse or epilepsy * Allergic to Florbetaben or any of its constituents * Multiple drug allergies and/or previous history of contrast allergy. * Pregnancy or breast feeding or planned pregnancy during the study period * Any disease or history of disease which, in the opinion of the investigator, can cause disturbance of brain function (e.g. vitamin B12 or folic acid deficiency, disturbed thyroid function) * Evidence for any other neurological or psychiatric disease