Genetical Interference and Gene Conversion

  • Robert K. Mortimer
  • Seymour Fogel


Gene conversion is a phenomenon associated with a high frequency of crossing-over of flanking markers (Mitchell, 1955; Case and Giles, 1964; Fogel and Hurst, 1967). Within a sample of 907 conversion events at four loci in the yeast Saccharomyces cerevisiae, 445 were associated with exchange of bracketing markers (Hurst et al., 1972). The finding that approximately 50% of the conversions were associated with crossing-over applied even when the bracketing alleles were in the same gene as the converted alleles. These results imply a direct relationship between gene conversion and crossing-over. A variety of different models have been proposed to explain recombination as a sequence of molecular events that may result in conversion alone, postmeiotic segregation, or either of these events associated with reciprocal recombination of outside markers (for review see Radding, 1973). A corollary of these models is that a reciprocal recombination event implies the occurrence of a conversion event somewhere between the recombined markers (Fogel and Mortimer, 1969; Paszewski, 1970). However, most and possibly all current models do not address themselves to the question of chiasma interference or the distribution of conversions and/or recombinations in adjacent genetic intervals.


Gene Conversion Adjacent Region Flank Marker Conversion Event Adjacent Interval 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Baranowska, A. 1970. Intragenic recombination pattern within the 164 locus of Ascobolus immersus in the presence of outside markers. Genet. Res. 16: 185.PubMedCrossRefGoogle Scholar
  2. Case, M. E. and N. H. Giles. 1964. Allelic recombination in Neurospora: Tetrad analysis of a three-point cross within the pan-2 locus. Genetics 49: 529.PubMedGoogle Scholar
  3. Fogel, S. and D. D. Hurst. 1967. Meiotic gene conversion in yeast tetrads and the theory of recombination. Genetics 57: 455.PubMedGoogle Scholar
  4. Fogel, S. and R. K. Mortimer. 1969. Informational transfer in meiotic gene conversion. Proc. Nat. Acad. Sci. U.S.A. 62: 96.CrossRefGoogle Scholar
  5. Fogel, S., D. D. Hurst and R. K. Mortimer. 1971. Gene conversion in unselected tetrads from multipoint crosses. In (G. Kimber and F. P. Rédei, eds.) Stadler Genetics Symposia, Vols. 1 and 2, pp. 89–110. University of Missouri Agriculture Experiment Station, Columbia, Mo.Google Scholar
  6. Hawthorne, D. C. and R. K. Mortimer. 1960. Chromsome mapping in Saooharomyoes: centromere-linked genes. Genetics 45: 1085.PubMedGoogle Scholar
  7. Holliday, R. 1964. A mechanism for gene conversion in fungi. Genet. Res. 5: 282.CrossRefGoogle Scholar
  8. Hurst, D. D., S. Fogel and R. K. Mortimer. 1972. Conversion-associated recombination in yeast. Proc. Nat. Acad. Sci. U.S.A. 69: 101.CrossRefGoogle Scholar
  9. Mitchell, M. B. 1955. Aberrant recombination of pyridoxine mutants of Neurospora. Proc. Nat. Acad. Sci. U.S.A. 41: 935.CrossRefGoogle Scholar
  10. Paszewski, A. 1967. A study on simultaneous conversions in linked genes in Ascobolus immersus. Genet. Res. 10: 121.PubMedCrossRefGoogle Scholar
  11. Paszewski, A. 1970. Gene Conversion: Observations on the DNA hybrid models. Genet. Res. 15: 55.PubMedCrossRefGoogle Scholar
  12. Radding, C. M. 1973. Molecular mechanisms in genetic recombination. Ann. Rev. Genet. 7: 87.PubMedCrossRefGoogle Scholar
  13. Stadler, D. R. 1959. The relationship of gene conversion to crossing-over in Neurospora. Proc. Nat. Acad. Sci. U.S.A. 45: 1625.CrossRefGoogle Scholar
  14. Stadler, D. R. 1973. The mechanism of intragenic recombination. Ann. Rev. Genet. 7 : 113.PubMedCrossRefGoogle Scholar
  15. Stadler, D. R., A. M. Towe and J. L. Rossignol. 1970. Intragenic recombination of ascospore color mutants in Ascobolus and its relationship to the segregation of outside markers. Genetics 66: 429.PubMedGoogle Scholar

Copyright information

© Plenum Press, New York 1974

Authors and Affiliations

  • Robert K. Mortimer
    • 1
  • Seymour Fogel
    • 1
  1. 1.Division of Medical Physics and Donner Laboratory, and Department of GeneticsUniversity of CaliforniaBerkeleyUSA

Personalised recommendations