Isolation and characterization of Df(3L)BSC875 Kim Cook and Kevin Cook Bloomington Stock Center Indiana University Df(3L)BSC875 was isolated as a FLP recombinase-induced recombination event involving P{XP}CG8600d02813 and PBac{WH}Ank2f02001. The deletion was isolated as a chromosome carrying two copies of the miniwhite marker in progeny of w1118; P{hs-hid}3, Dr1/TM6C, Sb1 cu1 females crossed to P{hsFLP}1, y1 w1118; P{XP}CG8600d02813/PBac{WH}Ank2f02001 males. The males were heat shocked as larvae as described in Parks et al., Nature Genetics 36: 288-292, 2004 (FBrf0175003). This cross and crosses in preceding and succeeding generations maintained the original genetic background of the Exelixis insertion stocks (Thibault et al., Nature Genetics 36: 283-287, 2004; FBrf0175002). The recombination event generated the genetic element P+PBac{XP3.WH3}BSC875 from the segment of P{XP}CG8600d02813 to the left of its FRT site and the segment of PBac{WH}Ank2f02001 to the right of its FRT site. The breakpoints of Df(3L)BSC875 predicted from the Release 5 genomic coordinates of the transposable element insertion sites are 3L:7328086 ;7654318 and the cytological breakpoints predicted from these coordinates are 65F5;66A8. Df(3L)BSC875 failed to complement smidC161 and Df(3L)Exel8104.