GENETIC INSTABILITY IN DROSOPHILA MELANOGASTER: THE INDUCTION OF SPECIFIC CHROMOSOME 2 DELETIONS BY MR ELEMENTS

Abstract

We describe the spontaneous induction of deletions by MR elements at the l(2)gl, net, pr and cn loci. The frequent induction of l(2)gl deletions mimics the high frequency of l(2)gl alleles found in wild populations of D. melanogaster. We suggest that these and other data that we present militate far the conclusion that, in the wild, autonomous MR elements occur and function as mutators. We contend that MR elements are not simply the by-products of hybridization between wild and laboratory strains.

AnSD(Segregation Distribution) –MR(Male Recombination) chromosome isolated from a natural population ofDrosophila melanogaster

“…This was especially a consideration since 3 of 5 presumptive en recombinants observed among the progeny of the S-90/cn bw males also appeared to be of Minute phenotype. On the basis of similar observations Green & Shepherd (1979) have suggested that they may be due to short deletions.…”