Intronic FGF14 GAA repeat expansions impact progression and survival in multiple system atrophy

Acknowledgements: We thank the participants and their families for their essential help with this work. We thank Dr Paul Lockhart for a kind gift of amplicons with FGF14 (GAA)n expansions in the pathological range. We also thank the Interdisciplinary Center for Biotechnology Research (ICBR) at University of Florida for contributing to long-read completion. Tissue samples and associated clinical and neuropathological data were supplied by the Queen Square Brain Bank, IBB-NeuroBiobank, CIBERNED Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas-Instituto de Salud Carlos III, the Multiple Sclerosis Society Tissue Bank (funded by the Multiple Sclerosis Society of Great Britain and Northern Ireland, registered charity 207495). We also thank Dr Gilbert Bensimon, Dr Christine Payan, Professor Ammar Al-Chalabi and the NNIPPS Consortium for access to the NNIPPS data. We also thank PROSPECT-M UK study for access to samples and data from clinically diagnosed MSA patients.