In humans, mutations in the Dsg2 gene are the underlying cause of the sudden death condition arrhythmogenic right ventricular cardiomyopathy [3]; Dsg2 serves as a receptor for adenoviruses that are involved in respiratory and urinary tract infections [4]; and Dsg2 has been identified as a regulator of β-amyloid protein processing in Alzheimer's disease [5]. Here, DSG2 is linked to Alzheimer disease.