14. Bell,A.C. and Felsenfeld,G. (2000) Methylation of a CTCF-dependent boundary controls imprinted expression of the Igf2 gene. Nature, 405, 482–485. 15. Hark,A.T., Schoenherr,C.J., Katz,D.J., Ingram,R.S., Levorse,J.M. and Tilghman,S.M. (2000) CTCF mediates methylation-sensitive enhancer-blocking activity at the H19/Igf2 locus. Nature, 405, 486–489. 16. Yu,W., Ginjala,V., Pant,V., Chernukhin,I., Whitehead,J., Docquier,F., Farrar,D., Tavoosidana,G., Mukhopadhyay,R. et al. (2004) Poly(ADP-ribosyl)ation regulates CTCF-dependent chromatin- insulation. Nat. Genet., 36, 1105–1110. 17. Chao,W., Huynh,K.D., Spencer,R.J., Davidow,L.S. and Lee,J.T. (2002) CTCF, a candidate trans-acting factor for X-inactivation choice. Science, 295, 345–347. 18. Valley,C.M. and Willard,H.F. (2006) Genomic and epigenomic approaches to the study of X chromosome inactivation. Curr. Opin. Genet. Dev., 16, 240–245. 19. Ling,J.Q., Li,T., Hu,J.F., Vu,T.H., Chen,H.L., Qiu,X.W., Cherry,A.M. and Hoﬀman,A.R. (2006) CTCF mediates interchromosomal colocalization between Igf2/H19 and Wsb1/Nf1. Science, 312, 269–272. 20. Kim,T.H., Abdullaev,Z.K., Smith,A.D., Ching,K.A., Loukinov,D.I., Green,R.D., Zhang,M.Q., Lobanenkov,V.V. and Ren,B. (2007) Analysis of the vertebrate insulator protein CTCF-binding sites in the human genome. Cell, 128, 1231–1245. 21. Mukhopadhyay,R., Yu,W., Whitehead,J., Xu,J., Lezcano,M., Pack,S., Kanduri,C., Kanduri,M., Ginjala,V. et al. (2004) The binding sites for the chromatin insulator protein CTCF map to DNA methylation-free domains genome-wide. Genome Res., 14, 1594–1602. 22. Xie,X., Mikkelsen,T.S., Gnirke,A., Lindblad-Toh,K., Kellis,M. and Lander,E.S. (2007) Systematic discovery of regulatory motifs in conserved regions of the human genome, including thousands of CTCF insulator sites. Proc. Natl Acad. Sci. USA, 104, 7145–7150. 23. Barski,A., Cuddapah,S., Cui,K., Roh,T.Y., Schones,D.E., Wang,Z., Wei,G., Chepelev,I. and Zhao,K. (2007) High-resolution proﬁling of histone methylations in the human genome. Cell, 129, 823–837. Nucleic Acids Research, 2008, Vol. 36, Database issue D87 24. Chung,J.H., Whiteley,M. and Felsenfeld,G. (1993) A 50 element of the chicken beta-globin domain serves as an insulator in human erythroid cells and protects against position eﬀect in Drosophila. Cell, 74, 505–514. 25. Kent,W.J. (2002) BLAT – The BLAST-Like Alignment Tool. Genome Res., 12, 656–664. 26. Sherry,S.T., Ward,M.H., Kholodov,M., Baker,J., Phan,L., Smigielski,E.M. and Sirotkin,K. (2001) dbSNP: the NCBI database of genetic variation. Nucleic Acids Res., 29, 308–311. 27. Sparago,A., Cerrato,F., Vernucci,M., Ferrero,G.B., Silengo,M.C. and Riccio,A. (2004) Microdeletions in the human H19 DMR result in loss of IGF2 imprinting and Beckwith-Wiedemann syndrome. Nat. Genet., 36, 958–960. 28. Prawitt,D., Enklaar,T., Gartner-Rupprecht,B., Spangenberg,C., Oswald,M., Lausch,E., Schmidtke,P., Reutzel,D., Fees,S. et al. (2005) Microdeletion of target sites for insulator protein CTCF in a chromosome 11p15 imprinting center in Beckwith-Wiedemann syndrome and Wilms’ tumor. Proc. Natl Acad. Sci. USA, 102, 4085–4090. 29. Karolchik,D., Baertsch,R., Diekhans,M., Furey,T.S., Hinrichs,A., Lu,Y.T., Roskin,K.M., Schwartz,M., Sugnet,C.W. et al. (2003) The UCSC Genome Browser Database. Nucleic Acids Res., 31, 51–54. 30. Su,A.I., Wiltshire,T., Batalov,S., Lapp,H., Ching,K.A., Block,D., Zhang,J., Soden,R., Hayakawa,M. et al. (2004) A gene atlas of the mouse and human protein-encoding transcriptomes. Proc. Natl Acad. Sci. USA, 101, 6062–6067. 31. Schwartz,S., Kent,W.J., Smit,A., Zhang,Z., Baertsch,R., Hardison,R.C., Haussler,D. and Miller,W. (2003) Human-mouse alignments with BLASTZ. Genome Res., 13, 103–107. 32. Kent,W.J., Baertsch,R., Hinrichs,A., Miller,W. and Haussler,D. (2003) Evolution’s cauldron: duplication, deletion, and rearrangement in the mouse and human genomes. Proc. Natl Acad Sci. USA, 100, 11484–11489. 33. Schones,D.E., Smith,A.D. and Zhang,M.Q. (2007) Statistical signiﬁcance of cis-regulatory modules. BMC Bioinformatics, 8, 19. 34. Ohlsson,R., Renkawitz,R. and Lobanenkov,V. (2001) CTCF is a uniquely versatile transcription regulator linked to epigenetics and disease. Trends Genet., 17, 520–527. 35. Altschul,S.F., Gish,W., Miller,W., Meyers,E.W. and Lipman,D.J. (1990) Basic Local Alignment Search Tool. J. Mol. Biol., 215, 403.