Thus, the diagnosis of AD within the clinical routine is based on a time consuming combination of psychological testing, imaging and the analysis of three well-established biomarkers (amyloid-β42 (Aβ42), total tau and phospho-tau-181) in cerebrospinal fluid (CSF) (Blennow 2005; Blennow et al. 2010; Zetterberg et al. 2010; Tapiola et al. 2009; Dubois et al. 2007). The gene discussed is MAPT; the disease is Alzheimer disease.