DYRK1A and Alzheimer disease: In addition to its significance in DS, the overexpression or hyperactivity of DYRK1A has been also reported in the brains of individuals diagnosed with any one of several neurodegenerative diseases, including AD, Parkinson's, Huntington's and Pick's (Ferrer et al., 2005; Kang et al., 2005; Kim et al., 2006).