Emmanouil T. Dermitzakis 1, e,*, Alexandre Reymond 1, e, Nathalie Scamuffa 1, Catherine Ucla 1, Ewen Kirkness 2, Colette Rossier 1, and Stylianos E. Antonarakis 1, *
1 Division of Medical Genetics and National Center of
Competence in Research (NCCR) Frontiers in Genetics, University of Geneva
Medical School and University Hospitals, 1211 Geneva, Switzerland.
2 The Institute for Genomic Research (TIGR), Rockville,
MD 20850, USA.
e These authors contributed equally to this work.
* To whom correspondence should be addressed.
E-mail: Stylianos.Antonarakis@medecine.unige.ch
(S.E.A.);
E-mail: Emmanouil.Dermitzakis@medecine.unige.ch
(E.T.D.)
Analysis of the human and mouse genomes identified an abundance of conserved non-genic sequences (CNGs). The significance and evolutionary depth of their conservation remain unanswered. We have quantified levels and patterns of conservation of 191 CNGs of human chromosome 21 in 14 mammalian species. We found that CNGs are significantly more conserved than protein-coding genes and noncoding RNAS (ncRNAs) within the mammalian class from primates to monotremes to marsupials. The pattern of substitutions in CNGs differed from that seen in protein-coding and ncRNA genes and resembled that of protein-binding regions. About 0.3% to 1% of the human genome corresponds to a previously unknown class of extremely constrained CNGs shared among mammals.
Additional References:
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4. Numata K, Kanai A, Saito R, Kondo S, Adachi J, Wilming LG, Hume DA, RIKEN GER Group, Arakawa T, Carninci P, Kawai J, Hayashizaki Y, and Tomita M, "Identification of Putative Noncoding RNAs among the RIKEN Mouse Full-Length cDNA Collection", Genome Research, vol. 13, no. 6b, pp. 1301-1306 (June 2, 2003).
5. Yuan G, Klämbt C, Bachellerie J-P, Brosius J and Hüttenhofer A, "RNomics in Drosophila melanogaster: Identification of 66 Candidates for Novel Non-messenger RNAs", Nucleic Acids Research, vol. 31, no. 10, pp. 2495-2507 (May 15, 2003).
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euchromatin: "the most active portion of the genome within the cell nucleus".