Research Fraud Bombshell Threatens Amyloid Hypothesis

by Jessica Hall

Alzheimer’s disease is a form of progressive dementia that we’ve labored to figure out for decades. Scientists made some headway with the amyloid hypothesis of Alzheimer’s disease, but progress is slow, and the hypothesis is incomplete. Now, a startling report has surfaced, accusing a prestigious Alzheimer’s researcher of systemic, deliberate research fraud. The results of this investigation could imperil the amyloid hypothesis as a whole.

The amyloid hypothesis of Alzheimer’s disease names a sticky protein called amyloid-beta as the disease’s primary cause. Scientists have identified “plaques and tangles” of amyloid-beta (Aβ) and tau (T) proteins in the brains of people who died of Alzheimer’s disease. But the amyloid hypothesis of the disease doesn’t fully explain its symptoms. Nor does it explain the scattershot absence of the protein in some Alzheimer’s victims’ brains.

But in 2006, Sylvain Lesné, of the University of Minnesota (UMN), shook up the Alzheimer’s research community with an extraordinary claim. Lesné and his team reported that they had discovered a “56-kDa soluble amyloid-β assembly,” a type of amyloid molecule which caused memory disruptions when they injected it into the brains of rats. (The “56-kDa” means 56 kiloDaltons, and it refers to the protein’s molecular…