Alzheimer's disease has two well-known primary causes, the misfolding or clumping of tau protein and amyloid beta. Amyloid beta, linked to cholesterol regulation within the brain, was the focus of both diagnostics and research into Alzheimer's.
Misfolded amyloid beta proteins build up around the neurons as a plaque, interfering with them and eventually killing them. But this mechanism is not the only culprit. A recent study has identified that tau protein is a much more crucial component of Alzheimer's.
Tau protein normally assists in the transport of materials within neurons and similar to amyloid beta, misfolded tau builds up and spreads throughout the brain leading to neuron death.
Alzheimer's disease was confirmed in 1375 brains out of the 3600 postmortem brains. The study showed that tau was in fact the driving force behind the disease though initially buildup of amyloid was the only clear indicator of cognitive decline. Malfunctioning tau seemed to spread from the memory centers of the brain outward into the cortex, mimicking the progression of the disease.
The study is a huge leap in Alzheimer's research but scientists recommend amyloid beta be part of Alzheimer's diagnostics and research till there is adequate evidence regarding tau protein.