Hur, Jae H.Van Doninck, KarineMandigo, Morgan L.Meselson, Matthew2009-09-282009Hur, Jae H., Karine Van Doninck, Morgan L. Mandigo, and Matthew Meselson. 2009. Degenerate tetraploidy was established before bdelloid rotifer families diverged. Molecular Biology and Evolution 26 (2):375-383.0737-4038http://nrs.harvard.edu/urn-3:HUL.InstRepos:3322470Rotifers of Class Bdelloidea are abundant freshwater invertebrates known for their remarkable ability to survive desiccation and their lack of males and meiosis. Sequencing and annotation of approximately 50-kb regions containing the four <i>hsp82</i> heat shock genes of the bdelloid <i>Philodina roseola</i>, each located on a separate chromosome, have suggested that its genome is that of a degenerate tetraploid. In order to determine whether a similar structure exists in a bdelloid distantly related to <i>P. roseola</i> and if degenerate tetraploidy was established before the two species separated, we sequenced regions containing the <i>hsp82</i> genes of a bdelloid belonging to a different family, <i>Adineta vaga</i>, and the histone gene clusters of <i>P. roseola</i> and <i>A. vaga</i>. Our findings are entirely consistent with degenerate tetraploidy and show that it was established before the two bdelloid families diverged and therefore probably before the bdelloid radiation.en-UShsp82Philodina roseolaAdineta vagahistone gene clusterJournal Article2009-09-2810.1093/molbev/msn260