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An Unusual 500,000 Bases Long Oscillation of Guanine and Cytosine Content in Human Chromosome 21

Wentian Li·Dirk Holste
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Abstract

An oscillation with a period of around 500 kb in guanine and cytosine content (GC%) is observed in the DNA sequence of human chromosome 21. This oscillation is localized in the rightmost one-eighth region of the chromosome, from 43.5 Mb to 46.5 Mb. Five cycles of oscillation are observed in this region with six GC-rich peaks and five GC-poor valleys. The GC-poor valleys comprise regions with low density of CpG islands and, alternating between the two DNA strands, low gene density regions. Consequently, the long-range oscillation of GC% result in spacing patterns of both CpG island density, and to a lesser extent, gene densities.

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Wentian Li, Dirk Holste. 2004-11-03. An Unusual 500,000 Bases Long Oscillation of Guanine and Cytosine Content in Human Chromosome 21. https://doi.org/10.1016/j.compbiolchem.2004.09.011

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