[ABSTRACT] Since the first descriptions of Familial Alzheimer Type Dementia during the 1930?s, a large number of pedigrees with an age at onset of less than 65 and a clear profile of Familial Alzheimer?s Disease with autosomic dominance genetic history has been reported in the literature. The majority of these families can be distributed into three groups that are carriers of specific gene mutations in chromosomes 21, 14 and 1. Researchers have also discovered a gene on chromosome 19 (APO E4) th