Currently fine-mapping studies of the MAPT H1/H2 clades have identified specific subhaplotypes associated with AD (Myers et al., 2005) and PSP (Pittman et al., 2005), while mostly conflicting results have been described with PD (Fung et al., 2006; Tobin et al., 2008; Vandrovcova et al., 2009; Seto-Salvia et al., 2011). Here, MAPT is linked to Alzheimer disease.