Non-methylated islands in fish genomes are GC-poor.
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ABSTRACT:
SUBMITTER: Cross S
PROVIDER: S-EPMC333903 | biostudies-other | 1991 Apr
REPOSITORIES: biostudies-other
Publications
Non-methylated islands in fish genomes are GC-poor.
Cross S S Kovarik P P Schmidtke J J Bird A A
Nucleic acids research 19910401 7
In the vertebrate genomes studied to date the 5' end of many genes are associated with distinctive sequences known as CpG islands. CpG islands have three properties: they are non-methylated; the dinucleotide CpG occurs at the frequency predicted by base composition; and they are GC-rich. Unexpectedly we have found that CpG islands in certain fish only have the first two properties; that is, their GC-content is not elevated compared to bulk genomic DNA. Based on this finding, we speculate that th ...[more]
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