FN Archimer Export Format PT J TI Transition from Environmental to Partial Genetic Sex Determination in Daphnia through the Evolution of a Female-Determining Incipient W Chromosome BT AF REISSER, Celine FASEL, Dominique HURLIMANN, Evelin DUKIC, Marinela HAAG-LIAUTARD, Cathy THUILLIER, Virginie GALIMOV, Yan HAAG, Christoph R. AS 1:1,2,3;2:2;3:2;4:4;5:2;6:2;7:5;8:1,2; FF 1:PDG-RBE-RMPF;2:;3:;4:;5:;6:;7:;8:; C1 CNRS Univ Montpellier Univ Paul Valery Montpellie, Ctr Ecol Fonct & Evolut CEFE UMR 5175, Montpellier, France. Univ Fribourg, Ecol & Evolut, Fribourg, Switzerland. IFREMER Centre du Pacifique, UMR 241 EIO, Labex CORAIL, BP 49, Taravao, Tahiti, Polynesie française Univ Basel, Inst Zool, Evolutionary Biol, Basel, Switzerland. Russian Acad Sci, Koltsov Inst Dev Biol, Moscow, Russia. C2 UNIV MONTPELLIER, FRANCE UNIV FRIBOURG, SWITZERLAND IFREMER, FRANCE UNIV BASEL, SWITZERLAND RUSSIAN ACAD SCI, RUSSIA SI TAHITI SE PDG-RBE-RMPF UM EIO IN WOS Ifremer jusqu'en 2018 copubli-france copubli-univ-france copubli-int-hors-europe IF 10.217 TC 11 UR https://archimer.ifremer.fr/doc/00376/48734/49098.pdf https://archimer.ifremer.fr/doc/00376/48734/89823.pdf LA English DT Article DE ;sex determination;sex chromosome;turnovers;gynodioecy;male sterility mutation;Daphnia magna AB Sex chromosomes can evolve during the evolution of genetic sex determination (GSD) from environmental sex determination (ESD). Despite theoretical attention, early mechanisms involved in the transition from ESD to GSD have yet to be studied in nature. No mixed ESD-GSD animal species have been reported, except for some species of Daphnia, small freshwater crustaceans in which sex is usually determined solely by the environment, but in which a dominant female sex-determining locus is present in some populations. This locus follows Mendelian single-locus inheritance, but has otherwise not been characterized genetically. We now show that the sex-determining genomic region maps to the same low-recombining peri-centromeric region of linkage group 3 (LG3) in three highly divergent populations of D. magna, and spans 3.6 Mb. Despite low levels of recombination, the associated region contains signs of historical recombination, suggesting a role for selection acting on several genes thereby maintaining linkage disequilibrium among the 36 associated SNPs. The region carries numerous genes involved in sex differentiation in other taxa, including transformer2 and sox9. Taken together, the region determining the genetic females shows characteristics of a sex-related supergene, suggesting that LG3 is potentially an incipient W chromosome despite the lack of significant additional restriction of recombination between Z and W. The occurrence of the female-determining locus in a pre-existing low recombining region illustrates one possible form of recombination suppression in sex chromosomes. D. magna is a promising model for studying the evolutionary transitions from ESD to GSD and early sex chromosome evolution. PY 2017 PD MAR SO Molecular Biology And Evolution SN 0737-4038 PU Oxford Univ Press VL 34 IS 3 UT 000396780600002 BP 575 EP 588 DI 10.1093/molbev/msw251 ID 48734 ER EF