The biochemistry of Alzheimer's disease (AD), one of the most common causes of adult dementia, is not yet very well understood. AD has been identified as a possible protein misfolding disease due to the accumulation of abnormally folded amyloid beta protein in the brains of Alzheimer's patients.[1] Amyloid beta, also written Aβ, is a short peptide that is an abnormal proteolytic byproduct of the transmembrane protein amyloid precursor protein (APP), whose function is unclear but thought to be involved in neuronal development.[2] The presenilins are components of proteolytic complex involved in APP processing and degradation.[3]