Hypothetical scenario of evolutionary events leading to glob2 and glob3 genes in drosophilids. The chromosomal localization and organisation of glob2, glob3 and glob2/3 genes and flanking regions in different subgroups of Drosophila phylogeny are displayed. [A] tandem duplication of glob2/3 gene; [B] separation of glob2 and glob 3 by transposition of glob 2 to Chr 2R (= Dme Chr 2L); [C] tandem glob2 and glob3, but chromosome breakage distal to the glob2-glob3 tandem; [D] transposition of glob2 to 3R 83 F4, 800 kb apart from glob3.
Gleixner et al. BMC Evolutionary Biology 2012 12:34 doi:10.1186/1471-2148-12-34