[Asn23]-beta-Amyloid (1-42), Iowa mutation, is a biologically active peptide exhibiting increased aggregation propensity and fibril toxicity. This mutation involves the substitution of Aspartic acid (Asp) at position 23 with Asparagine (Asn), contributing to autosomal dominant Alzheimer's Disease in various kindreds due to its association with severe cerebral amyloid beta-protein angiopathy (CAA). Specifically, the mutation is a missense alteration at position 694 of the amyloid precursor protein (APP) gene.