Unraveling the molecular pathway of Alzheimer's disease: research about presenilins gathers momentum.

Missense mutations of the presenilins (PS1 and PS2) first identified about one year ago are responsible for the majority of autosomal dominant familial Alzheimer's disease cases. Recent studies suggesting that these mutations exert their disastrous effect by elevating the levels of the longer form of beta-amyloid (A beta 42) are reviewed.