title: Genetics of an unstable white mutant in Drosophila simulans: reversion, suppression and somatic instability.
abstract: A spontaneous white mutation, white-milky (wmky) of Drosophila simulans is moderately unstable and is associated with a 16-kb long DNA insertion into the white gene. wmky, which is an unstable mutation found in D. simulans, has been genetically analyzed. Among nine spontaneous, partial reversions toward wild type, five were white locus mutations. They are phenotypically different from each other and three show eye color sexual dimorphism indicating a failure of the dosage compensation mechanism. Two w locus mutations whose eye color appeared identical between males and females were also isolated. Of the other back-mutants, three were associated with a recessive suppressor of wmky and one was a semidominant suppressor. These suppressor loci are located on the third chromosome at map positions about 90 and 120, respectively. The suppressor mutations demonstrate specific effects on w locus mutations derived from wmky which lack in the gene dosage compensation. Somatic instability was detected at the frequency of 5.6 X 10(-4) in wmky flies heterozygous for the recessive suppressor and the frequency was increased 10-fold when the suppressor mutation was placed in a different genetic background.
authors.affiliation: Department of Cell Genetics, National Institute of Genetics, Mishima, Japan.
authors.forename: Y H
authors.initials: YH
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Taira
authors.forename: M T
authors.initials: MT
authors.lastname: Yamamoto
mesh_terms: D000483:Alleles; D000818:Animals; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics; D004251:DNA Transposable Elements; D004330:Drosophila / Q000235:genetics*; D005123:Eye; D009030:Mosaicism; D009154:Mutation; D009693:Nucleic Acid Hybridization; D010641:Phenotype; D010858:Pigmentation; D013489:Suppression, Genetic
chemical_list: D004251:DNA Transposable Elements; D004247:DNA