A team of researchers has discovered that the protein that forms plaques in the brain in Alzheimer's disease also accumulates in the eyes of people with Down syndrome. The new findings in Down syndrome show that the toxic protein, known as amyloid-beta, that causes Alzheimer's pathology in the brain also leads to distinctive cataracts in the eyes. The discovery is leading the researchers to develop an innovative eye test for early detection of Alzheimer's pathology in both disorders.