MAPT and early-onset autosomal dominant Alzheimer disease: For example, natively unfolded proteins such as tau and β-amyloid aggregate in Alzheimer’s disease whereas globular proteins rich in β-sheets like transthyretin, rich in α-helices such as apolipoprotein A1 or containing both β-sheets and α-helices such as gelsolin aggregate in different types of systemic amyloidosis (Uversky et al., 2006).