Abstract
The microtubule associated protein tau is the key component of the neurofibrillary pathology seen in Alzheimer’s disease (AD) and other rare causes of dementia. Increased understanding of the physiology and pathophysiology of tau has opened up the possibility of targeting this molecule for therapeutic purposes in AD and related disorders. Two principal lines of investigation have been pursued: preventing the hyperphosphorylation of tau molecules, which is observed in tau extracted from AD brain; and preventing the aggregation of tau molecules into the paired helical filaments (PHFs), which constitute neurofibrillary change. The discovery of tau gene mutations as a rare cause of neurodegenerative disease has added impetus to research in this area.