The Bri2 protein, associated with Familial British and Danish dementias, comprises a β-rich BRICHOS domain40 which inhibits secondary nucleation and elongation during Aβ fibrillization,41 reducing Aβ neurotoxicity in a Drosophila model.42 Recombinant Bri2-BRICHOS (henceforth referred to as Bri2 in this study) forms both monomers, dimers and oligomers. Here, ITM2B is linked to dementia.