PAGE 11 OF 12 Nucleic Acids Research, 2012, Vol. 40, No. 4 e29 J. Bingham, E. Schadt, O. Banerjee, and D. Webster for helpful discussions. We thank Dr. E. Mahenthiralingam for the gift of Burkholderia cepacia J2315 DNA. FUNDING National Institutes of Health (grants 1RC2HG005618-01; National Human Genome Research Institute (NHGRI) and 1RC2GM092602-01; National Institute of General Medical Sciences (NIGMS)). Funding for open access charge: Internal funds of Paciﬁc Biosciences. Conﬂict of interest statement. T.A.C., A.O.K., K.E.S., M.B. and J.K. are full-time employees at Paciﬁc Biosciences, a company commercializing single-molecule, real-time nucleic acid sequencing technologies. I.A.M., R.D.M., A.F. and R.J.R. are full-time employees of New England Biolabs, a company that sells research reagents such as DNA methyltransferases. REFERENCES 1. Malone,T., Blumenthal,R.M. and Cheng,X. 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