Genetic Association of a Cystatin C Gene Polymorphism With Late-Onset Alzheimer Disease

Abstract

ALZHEIMER DISEASE (AD) is the major cause of dementia in the elderly. Familial forms of early-onset AD are caused by heterozygous mutations in the genes encoding the β-amyloid precursor protein (APP) and the presenilins PS1 and PS2, but the etiology of the much more prevalent forms of late-onset AD is unknown.^1-6 Several susceptibility genes were reported to influence the risk of developing AD; of these, the effect of the apolipoprotein E gene (APOE) is now uniformly accepted, whereas additional putative genetic risk factors including α₂-macroglobulin, interleukin 6, interleukin 1, and cathepsin D are matter of intense debate.^7-14