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Root MJ, Hamer DH.Root MJ, et al.Proc Natl Acad Sci U S A. 2003 Apr 29;100(9):5016-21. doi: 10.1073/pnas.0936926100. Epub 2003 Apr 17.Proc Natl Acad Sci U S A. 2003.PMID: 12702763Free PMC article.