I did not know until recently that humans are the only animals known to get Alzheimer's disease. Apparently, event chimps do not get it. So, the mice used in the study mentioned last week, had to be genetically altered to mimic the symptoms of the disease even though they really don't get it.
Scientists need to be able to study human brain cells which will develop Alzheimer's disease to really begin to get a better understanding of the cause and progression of the disease. Acquiring human brain cells for study is problematic. Cells from a deceased donor will not continue functioning or may be too far damaged by the disease to allow study to reveal the cause of the disease. Cells from a living donor are problematic because you risk damaging the person's brain. To acquire viable human brain cells, scientists have started converting human skin cells to stem cells which are then converted into human brain cells. Donations of skin are coming from individuals who are at high risk for Alzheimer's as well as those who are not.
Chemical Marker May Predict Cognitive Decline Risk
3-D Microscopy to Aid in Cell Analysis