31:
1336:
61:
852:
Bachtrog, Doris; Mank, Judith E.; Peichel, Catherine L.; Kirkpatrick, Mark; Otto, Sarah P.; Ashman, Tia-Lynn; Hahn, Matthew W.; Kitano, Jun; Mayrose, Itay; Ming, Ray; Perrin, Nicolas; Ross, Laura; Valenzuela, Nicole; Vamosi, Jana C. and The Tree of Sex
Consortium;
776:
Sember, Alexandr; Pappová, Michaela; Forman, Martin; Nguyen, Petr; Marec, František; Dalíková, Martina; Divišová, Klára; Doležálková-Kaštánková, Marie; Zrzavá, Magda; Sadílek, David; Hrubá, Barbora; Král, Jiří (24 July 2020).
458:) is a system that some species of insects, arachnids, and mammals use to determine the sex of offspring. In this system, there is only one sex chromosome, referred to as X. Males only have one
672:
XO sex determination can evolve from XY sex determination within about 2 million years. It typically evolves due to Y-chromosome degeneration. As the Y-chromosome is not paired (though see
1015:
Kobayashi, Tsuyoshi; Yamada, Fumio; Hashimoto, Takuma; Abe, Shintaro; Matsuda, Yoichi; Kuroiwa, Asato (2007). "Exceptional minute sex-specific region in the XO mammal, Ryukyu spiny rat".
1163:
970:
Denys, C.; Kadjo, B.; Missoup, A. D.; Monadjem, A.; Aniskine, V. (2013). "New records of bats (Mammalia: Chiroptera) and karyotypes from
Guinean Mount Nimba (West Africa)".
898:
Devlin, R.H. and Y. Nagahama, 2002. ‘Sex determination and sex differentiation in fish: an overview of genetic, physiological, and environmental influences’;
1156:
596:, producing both eggs and sperm with which they can fertilize themselves, while rare individuals are male and have only one sex chromosome (XO). The
1149:
470:
always contain an X chromosome, so the sex of the animals' offspring depends on whether a sex chromosome is present in the male gamete. Its
911:
Anderson, Luís Alves; Oliveira, Claudio; Nirchio, Mauro; Granado, Ángel and
Foresti, Fausto; ‘Karyotypic relationships among the tribes of
17:
854:
1255:
741:
122:
1202:
1078:
1106:"Lack of Detectable Genetic Recombination on the X Chromosome During the Parthenogenetic Production of Female and Male Aphids"
1088:
954:
721:
562:
437:
1104:
Hales, Dinah F.; Alex C. C. Wilson; Mathew A. Sloane; Jean-Christophe Simon; Jean-François
Legallic; Paul Sunnucks (2002).
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304:
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371:
181:
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688:
684:
117:
112:
102:
779:"Patterns of Sex Chromosome Differentiation in Spiders: Insights from Comparative Genomic Hybridisation"
702:
with XO sex-determination can occur by different mechanisms to produce either male or female offspring.
314:
176:
1370:
1285:
1207:
430:
166:
1365:
1235:
1172:
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Most spiders have a variation of the XO system in which males have two different X chromosomes (X
361:
1190:
1176:
716:
673:
601:
282:
277:
85:
80:
30:
584:
381:
1219:
1103:
644:). Some spiders have more complex systems involving as many as 13 different X chromosomes.
462:(XO), while females have two (XX). The letter O (sometimes a zero) signifies the lack of a
423:
321:
937:
Hsu, T. C.; Benirschke, Kurt (1977). "Hypsignathus monstrosus (Hammer-headed fruit bat)".
8:
677:
202:
1141:
1060:
1040:
997:
805:
778:
326:
309:
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188:
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1084:
1032:
950:
837:
810:
558:
331:
139:
134:
75:
1001:
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In a variant of this system, most individuals have two sex chromosomes (XX) and are
1214:
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987:
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923:) with description of XO sex chromosome system in a Neotropical fish species’;
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127:
855:‘Sex Determination: Why So Many Ways of Doing It?’; PLoS Biol12(7): e1001899
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normally contains either one X chromosome or no sex chromosomes at all.
649:
539:
535:
505:
497:
493:
60:
992:
653:
species have XO males. These are thought to arise via the loss of the
548:
543:
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501:
248:
228:
216:
1311:
606:
531:
482:
265:
467:
233:
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1289:
609:
frequently used in biological research—is one such organism.
1014:
660:
In humans the XO designation attaches to individuals with
1171:
969:
775:
51:
868:"Advances in Chromosomal Studies of Gastropod Molluscs"
485:
with the exception of mites where a small majority are
27:
Biological system that determines the sex of offspring
477:This system determines the sex of offspring among:
34:
Heredity of sex chromosomes in XO sex determination
1059:
1352:
865:
1057:
1157:
936:
431:
771:
769:
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687:is susceptible to decay, resulting in a ZZ/
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1121:
1097:
991:
883:
804:
794:
764:
821:
29:
1058:Patterson, J. T.; Stone, W. S. (1952).
834:Evolution of sex determining mechanisms
742:Temperature-dependent sex determination
14:
1353:
1203:Development of the reproductive system
1145:
722:Haplodiploid sex-determination system
866:Thirot-Quiévreux, Catherine (2003).
557:A few species of bat, including the
1076:
24:
694:
620:O), while females have a pair of X
563:Buettikofer's epauletted fruit bat
25:
1382:
1062:Evolution in the Genus Drosophila
939:An Atlas of Mammalian Chromosomes
683:Similarly, the W chromosome in a
676:), it is susceptible to decay by
1335:
1334:
212:Evolution of sexual reproduction
59:
1070:
1051:
567:Franquet's epauletted fruit bat
1008:
963:
930:
905:
892:
859:
846:
305:Sexual reproduction in animals
13:
1:
1077:Nei, Masatoshi (2013-05-02).
757:
571:Peters's epauletted fruit bat
1317:Disorders of sex development
984:10.1080/11250003.2013.775367
872:Journal of Molluscan Studies
667:
575:Gambian epauletted fruit bat
554:Several mammals, including:
182:Simultaneous hermaphroditism
7:
1083:. OUP Oxford. p. 168.
947:10.1007/978-1-4615-6436-2_4
737:ZW sex-determination system
732:ZO sex-determination system
727:XY sex-determination system
705:
685:ZW sex-determination system
624:chromosomes and a pair of X
456:X0 sex-determination system
452:XO sex-determination system
18:X0 sex-determination system
10:
1387:
972:Italian Journal of Zoology
927:, vol. 128 (2006); pp. 1-9
454:(sometimes referred to as
315:Penile-vaginal intercourse
177:Sequential hermaphroditism
1361:Sex-determination systems
1330:
1299:
1228:
1183:
1123:10.1017/S0016672302005657
1080:Mutation-Driven Evolution
1029:10.1007/s10577-006-1093-y
167:Testis-determining factor
1236:Sex-determination system
712:Sex-determination system
160:Sex chromosome anomalies
98:Sex-determination system
885:10.1093/mollus/69.3.187
546:, notably in the genus
1284:Sex determining gene:
1191:Sexual differentiation
1066:. New York: Macmillan.
717:Sexual differentiation
674:pseudoautosomal region
602:Caenorhabditis elegans
283:Internal fertilization
278:External fertilization
81:Sexual differentiation
35:
1256:Temperature-dependent
796:10.3390/genes11080849
585:Tokunoshima spiny rat
123:Temperature-dependent
33:
1220:Paramesonephric duct
1017:Chromosome Research
300:Fungal reproduction
203:Sexual reproduction
941:. pp. 13–16.
540:gastropod molluscs
327:Human reproduction
310:Sexual intercourse
295:Plant reproduction
189:Intersex (biology)
36:
1348:
1347:
1173:Sex determination
1110:Genetics Research
1090:978-0-19-163781-0
956:978-1-4684-7997-3
559:hammer-headed bat
448:
447:
332:Lordosis behavior
135:Heterogametic sex
76:Sexual dimorphism
16:(Redirected from
1378:
1371:Arachnid anatomy
1338:
1337:
1215:Mesonephric duct
1166:
1159:
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857:
850:
844:
832:Bull, James J.;
830:
819:
818:
808:
798:
773:
678:Muller's ratchet
581:Ryukyu spiny rat
440:
433:
426:
362:Animal sexuality
290:Sexual selection
68:Biological terms
63:
38:
37:
21:
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1366:Insect genetics
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1177:differentiation
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700:Parthenogenesis
697:
695:Parthenogenesis
670:
662:Turner syndrome
643:
639:
635:
631:
627:
623:
619:
615:
515:insects (e.g.,
500:insects (e.g.,
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377:Differentiation
367:Human sexuality
357:Plant sexuality
244:Spermatogenesis
140:Homogametic sex
28:
23:
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12:
11:
5:
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1268:Sex chromosome
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1138:
1137:
1116:(3): 203–209.
1096:
1089:
1069:
1050:
1023:(2): 175–187.
1007:
978:(2): 279–290.
962:
955:
929:
904:
891:
878:(3): 187–201.
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739:
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724:
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628:chromosomes (X
625:
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598:model organism
594:hermaphroditic
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145:Sex chromosome
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1341:
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1323:
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1310:
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1307:Hermaphrodite
1305:
1304:
1302:
1298:
1291:
1287:
1283:
1279:
1276:
1274:
1271:
1270:
1269:
1266:
1262:
1261:Haplodiploidy
1259:
1257:
1254:
1252:
1249:
1247:
1244:
1242:
1239:
1238:
1237:
1234:
1233:
1231:
1229:Genetic basis
1227:
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948:
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933:
926:
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918:
914:
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902:208: 191–364.
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469:
465:
461:
457:
453:
441:
436:
434:
429:
427:
422:
421:
419:
418:
413:
412:Hermaphrodite
410:
408:
405:
403:
400:
399:
398:
397:
394:
393:Sexual system
391:
390:
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369:
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337:Pelvic thrust
335:
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273:Fertilization
271:
267:
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258:
257:
254:
250:
247:
245:
242:
241:
240:
239:Gametogenesis
237:
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223:
220:
218:
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213:
210:
209:
208:
207:
204:
201:
200:
195:
192:
190:
187:
183:
180:
178:
175:
174:
173:
172:Hermaphrodite
170:
168:
165:
161:
158:
156:
153:
151:
148:
147:
146:
143:
141:
138:
136:
133:
129:
128:Haplodiploidy
126:
124:
121:
119:
116:
114:
111:
109:
106:
104:
101:
100:
99:
96:
92:
89:
87:
84:
83:
82:
79:
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71:
67:
66:
62:
58:
57:
54:
53:
49:
48:
44:
40:
39:
32:
19:
1322:Sex reversal
1278:Y chromosome
1273:X chromosome
1113:
1109:
1099:
1079:
1072:
1061:
1053:
1020:
1016:
1010:
975:
971:
965:
938:
932:
924:
921:Loricariidae
920:
917:Siluriformes
916:
913:Hypostominae
912:
907:
899:
894:
875:
871:
861:
848:
833:
786:
782:
752:Y chromosome
747:X chromosome
698:
682:
671:
659:
655:Y chromosome
648:
646:
611:
600:
591:
547:
517:grasshoppers
513:exopterygote
487:haplodiploid
476:
466:. Maternal
464:Y chromosome
460:X chromosome
455:
451:
449:
261:spermatozoon
155:Y chromosome
150:X chromosome
107:
91:Virilization
86:Feminization
50:
900:Aquaculture
536:crustaceans
525:cockroaches
502:dragonflies
498:Paleopteran
492:Almost all
407:Gonochorism
194:Mating type
1355:Categories
993:2263/42399
842:0805304002
789:(8): 849.
758:References
650:Drosophila
506:silverfish
494:apterygote
322:Copulation
1288:(mammal)
689:ZO system
668:Evolution
549:Ancistrus
544:bony fish
532:nematodes
483:arachnids
372:Mechanics
348:Sexuality
249:Oogenesis
229:Germ cell
217:Anisogamy
1340:Category
1312:Intersex
1300:See also
1184:Overview
1132:12220127
1037:17294259
1002:55842692
925:Genetica
836:; p. 17
815:32722348
706:See also
607:nematode
521:crickets
382:Activity
43:a series
41:Part of
1292:(birds)
1045:6461447
806:7466014
468:gametes
234:Meiosis
222:Isogamy
1208:gonads
1196:humans
1130:
1087:
1043:
1035:
1000:
953:
840:
813:
803:
573:, and
542:, and
402:Dioecy
256:Gamete
1290:DMRT1
1041:S2CID
998:S2CID
783:Genes
647:Some
530:Some
511:Most
481:Most
472:sperm
1175:and
1128:PMID
1085:ISBN
1033:PMID
951:ISBN
838:ISBN
811:PMID
583:and
579:The
496:and
450:The
266:ovum
1286:SRY
1118:doi
1025:doi
988:hdl
980:doi
943:doi
880:doi
801:PMC
791:doi
605:—a
52:Sex
1357::
1251:ZW
1246:X0
1241:XY
1126:.
1114:79
1112:.
1108:.
1039:.
1031:.
1021:15
1019:.
996:.
986:.
976:80
974:.
949:.
919::
876:69
874:.
870:.
823:^
809:.
799:.
787:11
785:.
781:.
766:^
691:.
680:.
664:.
657:.
569:,
565:,
561:,
538:,
534:,
523:,
519:,
504:,
118:ZO
113:ZW
108:XO
103:XY
45:on
1165:e
1158:t
1151:v
1134:.
1120::
1093:.
1047:.
1027::
1004:.
990::
982::
959:.
945::
915:(
888:.
882::
817:.
793::
642:2
640:X
638:2
636:X
634:1
632:X
630:1
626:2
622:1
618:2
616:X
614:1
527:)
508:)
489:,
439:e
432:t
425:v
20:)
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