Natural History of Amyloid Deposition in Adults With Down Syndrome

Specific Aim 1: To assess and compare amyloid deposition (with PiB PET) in non-demented/functionally stable adults with DS across three age cohorts (30-39, 40-49, and >50 years of age).

Primary Hypothesis 1: At initial assessment, there will be a significantly higher prevalence of amyloid-positive (PiB+) subjects in each succeeding age cohort.

In addition, we will test the following secondary hypothesis:

Secondary Aim 1: To compare the presence or absence of the apolipoprotein-E4 allele to the retention of PiB in various brain areas of the DS subjects.

Secondary Hypothesis 1: At baseline, subjects who carry at least one Apolipoprotein-E4 (ApoE4) allele will show a higher prevalence of being PiB+.

Inclusion criteria

• Participant IQ at least 47 (based upon Stanford-Binet V Abbrev. Test Battery)
• Participant at least 30 years of age
• DSDS score indicating participant is asymptomatic for AD
• Reliable caregiver who is capable of providing correct information about the participant's clinical symptoms and history
• Agreement of caregiver and clinician that participant is able to cooperate with the protocol tasks
• Participant has provided assent (or consent) and/or parent/caregiver has provided informed consent

Exclusion criteria

• Participant is non-verbal or has extremely limited language skills
• Score within the "symptomatic" range on the DSDS
• Any significant disease or unstable medical condition that could affect neuropsychological testing
• Any problems with vision or hearing that could affect neuropsychological testing
• Participants in whom MRI is contraindicated
• Claustrophobia or prior failed experiences of completing MRI scans or blood draws
• Participant is pregnant or breast feeding
• History or other evidence of severe illness or other condition that would make the participant, in the opinion of the investigator, unsuitable for the study?