Nearly all of the presenilin-1 (PSEN-1) mutations are missense mutations le
ading to Alzheimer's disease (AD). The role of the mutation E318G (a substi
tution of glutamic acid to glycine) in the PSEN-1 is controversial. It has
been found both in AD patients and in non-demented control individuals. Usi
ng the polymerase chain reaction and the restriction fragment length polymo
rphism method, we screened for E318G mutation in a total of 16 familial (FA
D) cases, in 64 sporadic neuropathologically confirmed AD cases and in 270
non-demented controls including 35 neuropathologically confirmed individual
s. We detected the E318G mutation in four FAD cases, seven sporadic AD case
s and 10 control individuals with highly varying onset-ages. Odds rations f
or carrying the mutation were 7.6 and 3 in FAD and sporadic AD cases, respe
ctively. Our results suggest that this mutation could be a risk factor in t
he Finnish FAD and sporadic AD population. It may be in linkage disequilibr
ium with a pathogenic change somewhere else in the PSEN-1 gene or in close
proximity to the PSEN-1 gene. (C) 2000 Elsevier Science Ireland Ltd. All ri
ghts reserved.