Adult individuals with Down syndrome (DS) develop Alzheimer disease (AD). Whether there is a difference between AD in DS and AD regarding the structure of amyloid-β (Aβ) and tau filaments is unknown. Here we report the structure of Aβ and tau filaments from two DS brains. We found two Aβ₄₀ filaments (types IIIa and IIIb) that differ from those previously reported in sporadic AD and two types of Aβ₄₂ filaments (I and II) identical to those found in sporadic and familial AD. Tau filaments (paired helical filaments and straight filaments) were identical to those in AD, supporting the notion of a common mechanism through which amyloids trigger aggregation of tau. This knowledge is important for understanding AD in DS and assessing whether adults with DS could be included in AD clinical trials.

患有唐氏综合症 (DS) 的成年个体会患上阿尔茨海默病 (AD)。 DS 和 AD 中的 AD 之间在淀粉样蛋白-β (Aβ) 和 tau 丝结构方面是否存在差异尚不清楚。在这里，我们报告了两个 DS 大脑的 Aβ 和 tau 丝的结构。我们发现两种 Aβ ₄₀丝（IIIa 和 IIIb 型）与之前报道的散发性 AD 不同，两种 Aβ ₄₂丝（I 和 II）与散发性和家族性 AD 中发现的相同。 tau 丝（成对的螺旋丝和直丝）与 AD 中的相同，支持淀粉样蛋白触发 tau 聚集的常见机制的概念。这些知识对于了解 DS 中的 AD 以及评估是否可以将患有 DS 的成人纳入 AD 临床试验非常重要。