Nine brains belonging to early onset Alzheimer disease (E280A-PS1 mutation) affected individuals from Antioquia, Colombia, were analyzed by neuropathological standard techniques. All individuals were ascertained from genealogies descendents from a common ancestor that shows a dominant autosomical pattern of inheritance.All cases analyzed were carriers to the E280A-PS1 mutation. This type of mutation produce beta-amyloid deposits of 42 aminoacids in the CNS. The mean of onset age was 48.4 years with an average of evolution time of 7.55 years and a mean of death age of 56.55. Although, all the cases showed symmetrical atrophy and them was more severe in the hippocampal region, a definitive anterior pattern (temporo-frontal) was showed. The higher the time of evolution of disease the lower the brain weight.All types of senile plaques and abundant neurofibrillary tanggles were found. In the stem, similar lesions were found but they were in lower number. Only the mesencephalic region showed a significative positive correlation between the number of senile plaques and the number of neurofibrillary tanggels (p < 0.05, r = 0.76). Only the parietal region showed a significant positive correlation between the number of senile plaques and the disease evolution time (p < 0.02, r = 0.74). Particularly, the cerebellum only showed senile plaques but neurofibrillary degeneration was not observed. With the exception of the Hirano bodies, all findings traditionally described were observed.