Drosophila mutants to illustrate landmark studies. Drosophila mutants to illustrate landmark studies. (A,B) Wild-type (A) and Notch mutant (B) wings showing notched (arrow) wing blades. Figure reproduced from Casso et al., 2011, with copyright permission from the publisher. (C,D) Sex combs on the front legs of a male D. melanogaster (arrows in C) are magnified in D. In polycomb mutants, anterior/posterior patterning is disrupted, resulting in sex combs appearing also on the middle and hind legs. Reproduced under a Creative Commons license from Wikicommons and with permission from http://flymove.uni-muenster.de. See also Weigmann et al., 2003. (E,F) Suppression of eye color variegation, from Qi et al., 2006. Variegation of eye color (F; juxtaposition of patches of white and red) is suppressed in heterozygotes of a mutation in Su(var)3-9, a gene that encodes an enzyme that methylates lysine 9 of histone H3 (E; uniformly red). TM3 is a balancer chromosome and serves as a ‘wild type’ control. Reproduced with copyright permission from the publisher. Robert J. Duronio et al. Dis. Model. Mech. 2017;10:1381-1389 © 2017. Published by The Company of Biologists Ltd