ABCA7 and early-onset autosomal dominant Alzheimer disease: Adenosine triphosphate-binding cassette transporter subfamily A member 7 (ABCA7) has abundant evidence for its involvement in Alzheimer’s disease (AD) pathogenesis from human genomic and genetic investigations, AD animal models, functional brain imaging in live individuals and postmortem studies of the human brain [1,2,3,4,5].