ACT has been shown to promote Abeta polymerization in vitro and in vivo, and levels of ACT protein in plasma and cerebrospinal fluid from Alzheimer's patients have been found to correlate with progression of dementia.
We found that plasma ACT levels were elevated in AD patients compared with the control group (p = 0.01) and were associated with severity of AD dementia; there was a negative association with the Mattis Dementia Rating Scale (a global measure of cognition) and a positive association with the Clinical Dementia Rating Scale (a global functional assessment).
We conclude that unlike the general population, neither PS-1 nor ACT polymorphisms appear to have a similar detrimental effect on dementia in DS.Am.J. Med.Genet.(Neuropsychiatr.Genet.)88:616-620, 1999.