Summary
Unequal mitotic sister strand crossing over has been evoked to explain the occurrence of phenotypically bb - males in the progeny of phenotypically bobbed males during magnification. If this is the case, complementary bb 1 loci should be obtained together with the bb 1. To test this hypothesis we compared the frequency of bb lethal mutations in the sperms of bb males with the percentage of phenotypically bb + males obtained during magnification of these bb males. We then compared these values with those occurring in phenotypically bb + control males. We found that, while the number of bb + males obtained during magnification, though variable, is high, the bb lethal mutation occurs at a very low frequency in all the genetic conditions, whatever the phenotype of the parental male.
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Communicated by Ch. Auerbach
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Malva, C., La Volpe, A. & Gargiulo, G. Comparison between rDNA magnification and bb lethal mutation frequencies in Drosophila melanogaster . Molec. Gen. Genet. 180, 511–515 (1980). https://doi.org/10.1007/BF00268054
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DOI: https://doi.org/10.1007/BF00268054