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Molecular evolution and recombination in gender-associated mitochondrial DNAs of the Manila clam Tapes philippinarum.

ABSTRACT: Doubly uniparental inheritance (DUI) provides an intriguing system for addressing aspects of molecular evolution and intermolecular recombination of mitochondrial DNA. For this reason, a large sequence analysis has been performed on Tapes philippinarum (Bivalvia, Veneridae), which has mitochondrial DNA heteroplasmy that is consistent with a DUI. The sequences of a 9.2-kb region (containing 29 genes) from 9 individuals and the sequences of a single gene from another 44 individuals are analyzed. Comparisons suggest that the two sex-related mitochondrial genomes do not experience a neutral pattern of divergence and that selection may act with varying strength on different genes. This pattern of evolution may be related to the long, separate history of M and F genomes within their tissue-specific "arenas." Moreover, our data suggest that recombinants, although occurring in soma, may seldom be transmitted to progeny in T. philippinarum.

SUBMITTER: Passamonti M

PROVIDER: S-EPMC1462575 | biostudies-other | 2003 Jun

REPOSITORIES: biostudies-other

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Molecular evolution and recombination in gender-associated mitochondrial DNAs of the Manila clam Tapes philippinarum.

Passamonti Marco M Boore Jeffrey L JL Scali Valerio V

Genetics 20030601 2

Doubly uniparental inheritance (DUI) provides an intriguing system for addressing aspects of molecular evolution and intermolecular recombination of mitochondrial DNA. For this reason, a large sequence analysis has been performed on Tapes philippinarum (Bivalvia, Veneridae), which has mitochondrial DNA heteroplasmy that is consistent with a DUI. The sequences of a 9.2-kb region (containing 29 genes) from 9 individuals and the sequences of a single gene from another 44 individuals are analyzed. C ...[more]

PMID: 12807780

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