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DNA structure-induced genomic instability in vivo.

ABSTRACT: Noncanonical DNA structures are postulated to be responsible for some breakpoint hotspots that occur frequently in cancers. We developed a novel mouse model system using the naturally occurring H-DNA structure that deviate from the familiar right-handed helical B form found at the breakage hotspot in the human c-MYC promoter and a Z-DNA-forming CG repeat to test this idea directly. Large-scale chromosomal deletions and/or translocations occurred in 5 (7.7%, 95% confidence interval [CI] = 3.7% to 12.8%) of the 65 mice carrying the H-DNA-forming sequences and in 7 (6.6%, 95% CI = 3.8% to 11.6%) of the 106 mice carrying the Z-DNA-forming sequences, but in 0 of the 63 control mice (P = .042 and P = .035, respectively, two-sided test). Thus, the DNA structure itself can introduce instability in a mammalian genome.

SUBMITTER: Wang G

PROVIDER: S-EPMC2639325 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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DNA structure-induced genomic instability in vivo.

Wang Guliang G Carbajal Steve S Vijg Jan J DiGiovanni John J Vasquez Karen M KM

Journal of the National Cancer Institute 20081209 24

Noncanonical DNA structures are postulated to be responsible for some breakpoint hotspots that occur frequently in cancers. We developed a novel mouse model system using the naturally occurring H-DNA structure that deviate from the familiar right-handed helical B form found at the breakage hotspot in the human c-MYC promoter and a Z-DNA-forming CG repeat to test this idea directly. Large-scale chromosomal deletions and/or translocations occurred in 5 (7.7%, 95% confidence interval [CI] = 3.7% to ...[more]

PMID: 19066276

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