Brain imaging can offer a window into risk for diseases such as Alzheimer's disease (AD). A study conducted at the University of Kansas School of Medicine demonstrated that genetic risk is expressed in the brains of even those who are healthy, but carry some risk for AD. The results of this study are published in the November 2009 issue of the Journal of Alzheimer's Disease. Investigators used automated neuroimaging（神经成像） analysis techniques to characterize the impact of an AD-risk gene, apolipoprotein（阿朴脂蛋白） E (ApoE4), on gray and white matter in the brains of cognitively（认知地，认识地） healthy elderly from the KU Brain Aging Project.

They found that healthy elderly individuals carrying a risk-allele（等位基因） of the ApoE4 gene had reduced cognitive performance, decreased brain volume in the hippocampus（海马） and amygdala（杏仁，扁桃腺） (regions important for memory processing), and decreased white matter integrity（诚实，正直） in limbic（边缘的） regions. These type of brain changes are also found in people with AD. Therefore, brain changes, usually found in AD patients, are also evident in nondemented individuals who have a genetic risk of later developing AD.

Lead investigator, Robyn Honea, DPhil, Research Assistant Professor, University of Kansas School of Medicine, Department of Neurology, Alzheimer's and Memory Group, comments, "It is important to note that findings of imaging phenotypes（表现型，显型） of risk variants, such as with this gene, have been shown in a number of studies. The unique element of our study is that we used several new neuroimaging analysis techniques. In addition, the individuals in our study have been well-characterized in a clinical setting."