Abstract
Autosomal dominant early-onset Alzheimer's disease (ADEOAD) is associated predominantly with mutations in the genes that codify for presenilin 1 (PSEN1). Only a few ADEOAD families have been reported from Latin America. This is an extended Chilean pedigree affected by ADEOAD along 4 generations. The age of onset of dementia was between 38 and 42 years. Early manifestations were anxiety and depression. Mutation analysis revealed a heterozygous G to C transversion at position 438 of the mRNA in PSEN1 in all affected members. This is the first report of a Chilean family with ADEOAD to include mutation analysis.