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The pseudoallelism of white and apricot in Drosophila melanogaster

Lewis, E. B. (1952) The pseudoallelism of white and apricot in Drosophila melanogaster. Proceedings of the National Academy of Sciences of the United States of America, 38 (11). pp. 953-961. ISSN 0027-8424.

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The classical example of multiple allelism is the series of eye-color mutants at the white (w) locus in Drosophila melanogaster. The altemative interpretation of this series, namely, that it is made up of "pseudoalleles," or closely linked genes with similar effects, has usually been considered ruled out by two kinds of evidence. In the first place early attempts to resolve the series by crossing over failed in spite of numerous tests involving most of the mutants available at the time.(1-4) Secondly, a heterozygote for two different mutant genes of the series does not have the phenotype expected for non-allelic genes, namely, wild-type (or red) eye color, but instead has a mutant eye color which is usually intermediate between the colors of the two respective homozygotes. In recent years, however, several cases have been found in which non-allelic genes give a positive phenotypic test for allelism by virtue of a position effect.(5-7) In such cases, which have been termed "position pseudoalleles,"(7) mutant genes at the different loci (say, a and b) give a mutant phenotype in the a +/+ b heterozygote, but a wild-type, or more nearly wild-type, phenotype in the a b/+ + heterozygote.

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Additional Information:Copyright © 1952 by the National Academy of Sciences. Communicated by A. H. Sturtevant, September 26, 1952. This study was aided by a contract with the Atomic Energy Commission operating through the Office of Naval Research, Department of the Navy, and the California Institute of Technology (NR 164010).
Issue or Number:11
Record Number:CaltechAUTHORS:LEWpnas52
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:1335
Deposited By: Tony Diaz
Deposited On:11 Jan 2006
Last Modified:02 Oct 2019 22:42

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