Df(3R)BSC841 was isolated as a FLP recombinase-induced recombination event involving P{XP}d03126 and PBac{WH}CG3563f00590. The deletion was isolated as a chromosome lacking miniwhite markers in progeny of w1118; P{hs-hid}3, Dr1/TM6C, Sb1 cu1 females crossed to P{hsFLP}1, y1 w1118; P{XP}d03126/PBac{WH}CG3563f00590 males. The males were heat shocked as larvae as described in Parks et al., Nature Genetics 36: 288-292, 2004 (FBrf0175003). The recombination event generated the genetic element P+PBac{XP5.WH5}BSC841 from the segment of P{XP}d03126 to the left of its FRT site and the segment of PBac{WH}CG3563f00590 to the right of its FRT site. Its presence was verified using the PCR methods and primers described in Parks et al. Exelixis, Inc. determined the insertion site of P{XP}d03126  to be Release 3 genomic coordinate 10384121 on chromosome arm 3R. This corresponds to 88C6 on the Release 3 and Release 5 genome maps. The predicted position of PBac{WH}CG3563f00590 on the Release 5 map is 88D2. Consequently, the cytological breakpoints of Df(3R)BSC841 are predicted to be 88C6;88D2. Df(3R)BSC841 is associated with dominant male sterility, which is likely caused by His4r haploinsufficiency (see Ryder et al., Genetics 177; 615-629, 2007; FBrf0202170). Df(3R)BSC841 failed to complement stumps09904b and put10460.