Genes known to increase the risk of Alzheimer’s may actually be an inherited form of the disorder, researchers say CNNAPOE4 homozygozity represents a distinct genetic form of Alzheimer’s disease Nature.comStudy Suggests Genetics as a Cause, Not Just a Risk, for Some Alzheimer's The New York TimesPeople with two copies of a risk gene have genetic form of Alzheimer's, scientists say ReutersAlzheimer's risk gene APOE4 may cause a distinct form of the disease, study suggests STAT