The following information accompanied fly stocks donated to the Stock Center (2/00) by Jan Eeken, Leiden University. An EMS screen for lethal mutations that fail to complement Df(2L)JS17 identified 14 complementation groups. The mutations were induced on a cn1 bw1 chromosome. Compl. group Allele Df mapping l(2)23Ca A16-1 Not included within Df(2L)JS7 or C28 l(2)23Cb A18-6 Not included within Df(2L)JS7 or C28 l(2)23Cc A17-2 Not included within Df(2L)JS7 or C28 l(2)23Cd A7-4 Not included within Df(2L)JS7 or C28 l(2)23Ce A6-2 Not included within Df(2L)JS7 or C28 l(2)23CDa A1-6 Included within Df(2L)JS7, but not Df(2L)C28 l(2)23CDb A1-5 Included within Df(2L)JS7, but not Df(2L)C28 l(2)23CDc A1-4 Included within Df(2L)JS7, but not Df(2L)C28 toc A1-1 Included within Df(2L)JS7, but not Df(2L)C28 l(2)23CDd A9-3 Included within Df(2L)JS7, but not Df(2L)C28 l(2)23CDe A8-1 Included within Df(2L)JS7, but not Df(2L)C28 l(2)23CDf A13-1 Included within Df(2L)JS7, but not Df(2L)C28 l(2)23Da A5-2 Included within Df(2L)C28, but not Df(2L)JS7 l(2)23Db A18-1 Included within Df(2L)C28, but not Df(2L)JS7 The relative positions of complementation groups within the three intervals is not known. l(2)23CaA16-1 is semilethal. This screen was described in Eeken, J.C., Kooistra, R., Lohman, P.H., Pastink, A. and Szakmary, A. 1997, Isolation and characterization of two MMS-sensitive mutants in region 23C-23D. A. Dros. Res. Conf. 38: 272A (FBrf0092383).