Additional Study Information: The purpose of this study is to better understand why certain patients are more likely to respond totreatment than others, to facilitate the development of personalized medicinesto get the rightmedicine to the right patient. To achieve this goal, samples of blood will be collected from patients with Alzheimer's for future research. The sample will be used by Genentech researchers and other researchers partnering with Genentech for future research related to Alzheimers disease and related diseases and/or the use of a study drug called crenezumab in disease therapy and diagnosis, and its side effects.