No evidence of APP point mutation and locus duplication in individuals with cerebral amyloid angiopathy.

Background:  Cerebral amyloid angiopathy (CAA) is a well-established cause of lobar intracerebral hemorrhage (ICH). Familial forms of CAA are because of mutations in the gene encoding the beta-amyloid precursor protein (APP) and duplications of this gene can cause early-onset Alzheimer’s disease associated with CAA. However, the contribution of APP genetic variants in the development of sporadic CAA remains unknown. Methods:  The presence of genetic variants in the APP was examined in 78 patients with CAA-related ICH by sequencing exons 16 and 17 coding the β-amyloid protein and analyzing the presence of possible duplications of APP by microsatellite analysis and quantitative PCR. Results:  We did not identify any pathogenic mutation or chromosomal duplication of APP. Conclusions:  Our results suggest that APP genetic variants, point mutations and locus duplication, are not a common cause of CAA-related ICH in the Spanish population.