Skip to main content
NCBI home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1991 Mar 15;88(6):2540–2544. doi: 10.1073/pnas.88.6.2540

Interspecific gene flow in sympatric oaks.

A T Whittemore 1, B A Schaal 1
PMCID: PMC51268  PMID: 11607170

Abstract

Variation of chloroplast DNA and nuclear ribosomal DNA (DNA encoding ribosomal RNA) was studied for five species of white oak native to the eastern United States. Although these species differ in many morphological characters and have different (though overlapping) geographical ranges and ecological tolerances, they are interfertile and often grow in mixed stands, and hybrids are occasionally found in nature. All individuals studied were morphologically typical members of their respective species-i.e., showed no evidence of recent hybrid ancestry. Restriction site markers in the chloroplast DNA reveal several clear cases of localized gene exchange between species, showing that there is appreciable gene flow between sympatric species in this group. One length variant of the nuclear ribosomal DNA, however, is species specific. The sharp morphological and ecological differences between the species, together with the one ribosomal DNA variant, suggest that nuclear genes may be exchanged less freely between species than are chloroplast genotypes.

Full text

PDF
2540

Images in this article

2542Image
on p.2542

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Barton N., Bengtsson B. O. The barrier to genetic exchange between hybridising populations. Heredity (Edinb) 1986 Dec;57(Pt 3):357–376. doi: 10.1038/hdy.1986.135. [DOI] [PubMed] [Google Scholar]
  2. Birky C. W., Jr, Fuerst P., Maruyama T. Organelle gene diversity under migration, mutation, and drift: equilibrium expectations, approach to equilibrium, effects of heteroplasmic cells, and comparison to nuclear genes. Genetics. 1989 Mar;121(3):613–627. doi: 10.1093/genetics/121.3.613. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Ferris S. D., Sage R. D., Huang C. M., Nielsen J. T., Ritte U., Wilson A. C. Flow of mitochondrial DNA across a species boundary. Proc Natl Acad Sci U S A. 1983 Apr;80(8):2290–2294. doi: 10.1073/pnas.80.8.2290. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Gyllensten U., Wilson A. C. Interspecific mitochondrial DNA transfer and the colonization of Scandinavia by mice. Genet Res. 1987 Feb;49(1):25–29. doi: 10.1017/s0016672300026690. [DOI] [PubMed] [Google Scholar]
  5. Keim P., Paige K. N., Whitham T. G., Lark K. G. Genetic analysis of an interspecific hybrid swarm of Populus: occurrence of unidirectional introgression. Genetics. 1989 Nov;123(3):557–565. doi: 10.1093/genetics/123.3.557. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Powell J. R. Interspecific cytoplasmic gene flow in the absence of nuclear gene flow: evidence from Drosophila. Proc Natl Acad Sci U S A. 1983 Jan;80(2):492–495. doi: 10.1073/pnas.80.2.492. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Rieseberg L. H., Beckstrom-Sternberg S., Doan K. Helianthus annuus ssp. texanus has chloroplast DNA and nuclear ribosomal RNA genes of Helianthus debilis ssp. cucumerifolius. Proc Natl Acad Sci U S A. 1990 Jan;87(2):593–597. doi: 10.1073/pnas.87.2.593. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Tegelström H. Transfer of mitochondrial DNA from the northern red-backed vole (Clethrionomys rutilus) to the bank vole (C. glareolus). J Mol Evol. 1987;24(3):218–227. doi: 10.1007/BF02111235. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES