Structure of ATTRv-F64S fibrils isolated from skin tissue of a living patient

Transthyretin-derived amyloidosis (ATTR) is a degenerative, systemic disease characterized by transthyretin fibril deposition in organs like the heart, kidneys, liver, and skin. We report the first cryo-EM structure of transthyretin fibrils isolated from skin tissue of a living patient with a rare genetic mutation (ATTRv F64S). The structure adopts a highly conserved fold previously observed in other ATTR fibrils from different tissues or genetic variants. Mass spectrometry was used to identify common post-translational modifications. The structural consistency between ATTR filaments validates non-invasive skin biopsy as a diagnostic tool.