A novel simple satellite DNA is colocalized with the Stalker retrotransposon in Drosophila melanogaster heterochromatin

In the T(1;2)dor( var7) multibreak rearrangement the distal 1A-2B segment o f the X chromosome of; Drosophila melanogaster is juxtaposed to an inverted portion of the heterochromatin of chromosome 2. Analysis of mitotic chromo somes by a series of handing techniques has permitted us precisely to locat e the heterochromatic breakpoint of this translocation in the h42 region of 2R. Cloning and sequencing of the eu-heterochromatic junction revealed tha t the translocated 1A-2B fragment is joined to (AACAC)(n) repeats, which re present a previously undescribed satellite DNA in D. melanogaster. These re peated sequences have been estimated to account for about 1 Mb of the D. me lanogaster genome. The repeats are located mainly in the Y chromosome and i n the heterochromatin of the right arm of chromosome 2 (2Rh), where they ar e colocalized with the Stanier retrotransposon.