A newly formed amyloidogenic fragment due to a stop codon mutation causes familial British dementia.
Familial British dementia (FBD) is an early-onset autosomal dominant disorder characterized by progressive cognitive impairment, spasticity, and cerebellar ataxia. Hippocampal neurofibrillar degeneration and widespread parenchymal and vascular amyloid deposits are the main neuropathological lesions. Amyloid fibrils are composed of a novel 34 amino acid subunit (ABri) with no sequence identity to any known amyloid molecule. The peptide derives from a larger precursor protein codified by a single gene BRI on chromosome 13. Affected family members have a single base substitution at the stop codon of the BRI gene that generates a longer open-reading frame resulting in a larger precursor protein. The release of the 34 C-terminal amino acids from the mutated precursor originates the ABri amyloid subunit. Our discovery of a new amyloid associated with the development of dementia supports the concept that amyloid peptides may be of primary importance in the initiation of neurodegeneration.
Ghiso
J
J
Department of Pathology, New York University School of Medicine, NY 10016, USA. ghisoj01@popmail.med.nyu.edu
Vidal
R
R
Rostagno
A
A
Mead
S
S
Révész
T
T
Plant
G
G
Frangione
B
B
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000682:Amyloid / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D001921:Brain / Q000473:pathology*; D002524:Cerebellar Ataxia / Q000235:genetics* / Q000473:pathology; D002531:Cerebellum / Q000473:pathology; D002874:Chromosome Mapping; D002882:Chromosomes, Human, Pair 13; D018388:Codon, Terminator; D003072:Cognition Disorders / Q000235:genetics* / Q000473:pathology; D003704:Dementia / Q000235:genetics* / Q000473:pathology; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D009128:Muscle Spasticity / Q000235:genetics; D009154:Mutation; D016366:Open Reading Frames; D010446:Peptide Fragments / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D011498:Protein Precursors / Q000737:chemistry / Q000235:genetics; D006113:United Kingdom
D048868:Adaptor Proteins, Signal Transducing; D000682:Amyloid; D018388:Codon, Terminator; C120083:ITM2B protein, human; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D010446:Peptide Fragments; D011498:Protein Precursors