U: unaffected relative; PP primary progressive MS; RR: relapsing- remitting MS; SP: secondary progressive MS; M: male; F: female; y: years; EDSS: expanded disability status scale; active: disease course with relapse within a year prior to sampling. None of the patients had diagnosed infections at the time of sampling. (DOC) Table S2 (DOC) Acknowledgments List of primers used in this study. We thank P. R. Thompson for the gift of Cl-amidine; A. A. Cook, T. Kouzarides, and M. Yamada for PADI4 cDNAs; the Department of Neurology, Aarhus University Hospital, Denmark, for mediating the blood samples; E. Allemand, B. Baron, and M. Vera Ugalde for technical advice and valuable discussion; and J. Seeler and A. Kumar for critical reading of the manuscript. References 1. Noseworthy JH, Lucchinetti C, Rodriguez M, Weinshenker BG (2000) Multiple sclerosis. N Engl J Med 343: 938–952. 2. 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