Isolation and characterization of Df(2R)BSC346 Stacey Christensen, Kimberley Cook and Kevin Cook Bloomington Stock Center Indiana University Df(2R)BSC346 was isolated as a FLP recombinase-induced recombination event involving PBac{WH}f04779 and P{XP}CG30089d01337. The deletion was isolated as a chromosome lacking miniwhite markers in progeny of P{hsFLP}1, y1 w1118; PBac{WH}f04779/P{XP}CG30089d01337 males crossed to w1118; P{hs-hid}2, wgSp-1/CyO females. These 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{XP5.WH5}BSC346 from the segment of PBac{WH}f04779 to the left of its FRT site and the segment of P{XP}CG30089d01337 to the right of its FRT site. Its presence was verified using the PCR methods and primers described in Parks et al. The cytological breakpoints of Df(2R)BSC346 predicted from the Release 5 genomic coordinates of the transposable element insertions sites are 51E7;52C2. It failed to complement dupPA77 and scb1.