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Circular DNA intermediates in the generation of large human segmental duplications.

ABSTRACT:

Background

Duplications of large genomic segments provide genetic diversity in genome evolution. Despite their importance, how these duplications are generated remains uncertain, particularly for distant duplicated genomic segments.

Results

Here we provide evidence of the participation of circular DNA intermediates in the single generation of some large human segmental duplications. A specific reversion of sequence order from A-B/C-D to B-A/D-C between duplicated segments and the presence of only microhomologies and short indels at the evolutionary breakpoints suggest a circularization of the donor ancestral locus and an accidental replicative interaction with the acceptor locus.

Conclusions

This novel mechanism of random genomic mutation could explain several distant genomic duplications including some of the ones that took place during recent human evolution.

SUBMITTER: Chicote JU

PROVIDER: S-EPMC7450558 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Circular DNA intermediates in the generation of large human segmental duplications.

Chicote Javier U JU López-Sánchez Marcos M Marquès-Bonet Tomàs T Callizo José J Pérez-Jurado Luis A LA García-España Antonio A

BMC genomics 20200826 1

<h4>Background</h4>Duplications of large genomic segments provide genetic diversity in genome evolution. Despite their importance, how these duplications are generated remains uncertain, particularly for distant duplicated genomic segments.<h4>Results</h4>Here we provide evidence of the participation of circular DNA intermediates in the single generation of some large human segmental duplications. A specific reversion of sequence order from A-B/C-D to B-A/D-C between duplicated segments and the ...[more]

PMID: 32847497

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