MoBio Gene Conversion Chapter 8

Gene conversion is a nonreciprocal transfer of genetic information. The following figure illustrates the difference between gene conversion and DNA crossover. An origin of gene conversion is explanined in Figure 8-D-5.

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Figure 8-D-4. Comparison between gene conversion and DNA crossover. (a) Two DNA molecules. (b) Gene conversion - the red DNA donates part of its genetic information (e-e' region) to the blue DNA. (c) DNA crossover - the two DNAs exchange part of their genetic information (f-f' and F-F').

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Figure 8-D-5. An origin of gene conversion. (a) Heteroduplexes formed by the resolution of Holliday structure or by other mechanisms. (b) The blue DNA uses the invaded segment (e') as template to "correct" the mismatch, resulting in gene conversion. (c) Both DNA molecules use their original sequences as template to correct the mismatch. Gene conversion does not occur.