Although there is no general agreement about the potential role of CA1 in AD diagnosis, it has been shown that the CSF tau and Aβ42 concentrations at baseline correlate with the rate of hippocampal atrophy and progressive inward deformations of the CA1 subfield in the individuals at the very mild stage of AD (Clinical Dementia Rating 0.5; Wang et al., 2012). This evidence concerns the gene MAPT and Alzheimer disease.