HOUSTON: Nobody knew each other’s name. Even so, 60 people who either were at risk of having an autosomal-dominant Alzheimer’s mutation, or were accompanying someone who was, exchanged information about a shared problem. There were moments of validation—“Denial has divided my family, too!”—and apprehensive questions—“Do you want to know if you have it?” Family speakers on the program addressed the audience anonymously. Hotel staff knew only that they were hosting a medical symposium.