[{"article_type":"original","OA_type":"gold","PlanS_conform":"1","day":"01","file":[{"access_level":"open_access","success":1,"creator":"dernst","content_type":"application/pdf","checksum":"f40abffa56cb1e9ff65800f2a7d7b39a","file_id":"20274","file_size":1239841,"file_name":"2025_MolecularBioEvolution_Mrnjavac.pdf","date_created":"2025-09-02T07:47:32Z","date_updated":"2025-09-02T07:47:32Z","relation":"main_file"}],"file_date_updated":"2025-09-02T07:47:32Z","DOAJ_listed":"1","tmp":{"short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"publication_identifier":{"issn":["0737-4038"],"eissn":["1537-1719"]},"fulldoi":"https://doi.org/10.1093/molbev/msaf177","acknowledged_ssus":[{"_id":"ScienComp"}],"citation":{"apa":"Mrnjavac, A., Vicoso, B., &#38; Connallon, T. (2025). An extension of Muller’s sheltering hypothesis for the evolution of sex chromosome gene content. <i>Molecular Biology and Evolution</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/molbev/msaf177\">https://doi.org/10.1093/molbev/msaf177</a>","mla":"Mrnjavac, Andrea, et al. “An Extension of Muller’s Sheltering Hypothesis for the Evolution of Sex Chromosome Gene Content.” <i>Molecular Biology and Evolution</i>, vol. 42, no. 8, msaf177, Oxford University Press, 2025, doi:<a href=\"https://doi.org/10.1093/molbev/msaf177\">10.1093/molbev/msaf177</a>.","ieee":"A. Mrnjavac, B. Vicoso, and T. Connallon, “An extension of Muller’s sheltering hypothesis for the evolution of sex chromosome gene content,” <i>Molecular Biology and Evolution</i>, vol. 42, no. 8. Oxford University Press, 2025.","ama":"Mrnjavac A, Vicoso B, Connallon T. An extension of Muller’s sheltering hypothesis for the evolution of sex chromosome gene content. <i>Molecular Biology and Evolution</i>. 2025;42(8). doi:<a href=\"https://doi.org/10.1093/molbev/msaf177\">10.1093/molbev/msaf177</a>","short":"A. Mrnjavac, B. Vicoso, T. Connallon, Molecular Biology and Evolution 42 (2025).","chicago":"Mrnjavac, Andrea, Beatriz Vicoso, and Tim Connallon. “An Extension of Muller’s Sheltering Hypothesis for the Evolution of Sex Chromosome Gene Content.” <i>Molecular Biology and Evolution</i>. Oxford University Press, 2025. <a href=\"https://doi.org/10.1093/molbev/msaf177\">https://doi.org/10.1093/molbev/msaf177</a>.","ista":"Mrnjavac A, Vicoso B, Connallon T. 2025. An extension of Muller’s sheltering hypothesis for the evolution of sex chromosome gene content. Molecular Biology and Evolution. 42(8), msaf177."},"oa":1,"scopus_import":"1","OA_place":"publisher","department":[{"_id":"BeVi"}],"type":"journal_article","related_material":{"link":[{"relation":"software","url":"https://git.ista.ac.at/bvicoso/xydegenerate"}]},"pmid":1,"month":"08","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","ddc":["570"],"oa_version":"Published Version","date_created":"2025-08-24T22:01:31Z","doi":"10.1093/molbev/msaf177","date_updated":"2025-09-30T14:25:57Z","publication":"Molecular Biology and Evolution","volume":42,"acknowledgement":"We thank Filip Ruzicka, Colin Olito, Akane Uesugi, Melissa Toups, Daniel Jeffries, the Associate Editor, and anonymous reviewers, for comments and suggestions on earlier versions of the paper. We are particularly grateful to Deborah Charlesworth and Brian Charlesworth for extensive comments on two different drafts of the manuscript. We also thank Aneil Agrawal and Thomas Lenormand for email correspondence about the data on dominance and ways to interpret it. Technical support was provided by ISTA Scientific Computing Unit.","intvolume":"        42","language":[{"iso":"eng"}],"status":"public","abstract":[{"text":"The first influential hypothesis for sex chromosome evolution was proposed in 1914 by H. J. Muller, who argued that once recombination was suppressed between the X and Y chromosomes, Y-linked genes become “sheltered” from selection, leading to accumulation of recessive loss-of-function (LOF) mutations and decay of Y-linked genes. The hypothesis fell out of favor in the 1970s because early mathematical models failed to support it and data on the dominance of lethal mutations were viewed as incompatible with the hypothesis. We reevaluate the main arguments against Muller's hypothesis and find that they do not conclusively exclude a role for sheltering in sex chromosome evolution. By relaxing restrictive assumptions of earlier models, we show that sheltering promotes fixation of LOF mutations with sexually dimorphic fitness effects, resulting in decay of X-linked genes that are exclusively expressed by males and Y-linked genes that are primarily, though not necessarily exclusively, expressed by females. We further show that drift and other processes contributing to Y degeneration (i.e. selective interference and regulatory evolution) expand conditions of Y-linked gene loss by sheltering. The actual contribution of sheltering to sex chromosome evolution hinges upon the distribution of dominance and sex-specific fitness effects of LOF mutations, which we discuss.","lang":"eng"}],"external_id":{"isi":["001547617100001"],"pmid":["40713898"]},"article_number":"msaf177","issue":"8","quality_controlled":"1","_id":"20223","publisher":"Oxford University Press","article_processing_charge":"Yes","author":[{"first_name":"Andrea","last_name":"Mrnjavac","id":"353FAC84-AE61-11E9-8BFC-00D3E5697425","full_name":"Mrnjavac, Andrea"},{"full_name":"Vicoso, Beatriz","id":"49E1C5C6-F248-11E8-B48F-1D18A9856A87","last_name":"Vicoso","orcid":"0000-0002-4579-8306","first_name":"Beatriz"},{"full_name":"Connallon, Tim","last_name":"Connallon","first_name":"Tim"}],"title":"An extension of Muller's sheltering hypothesis for the evolution of sex chromosome gene content","date_published":"2025-08-01T00:00:00Z","publication_status":"published","year":"2025","has_accepted_license":"1","isi":1},{"file_date_updated":"2025-03-10T08:25:59Z","file":[{"success":1,"access_level":"open_access","date_created":"2025-03-10T08:25:59Z","date_updated":"2025-03-10T08:25:59Z","relation":"main_file","file_size":768371,"file_name":"2025_GBE_Mrnjavac.pdf","file_id":"19378","checksum":"e3aa993e3d6dad10cb806c243fa57408","content_type":"application/pdf","creator":"dernst"}],"day":"01","article_type":"original","OA_type":"gold","OA_place":"publisher","oa":1,"scopus_import":"1","fulldoi":"https://doi.org/10.1093/gbe/evaf021","citation":{"short":"A. Mrnjavac, B. Vicoso, Genome Biology and Evolution 17 (2025).","ista":"Mrnjavac A, Vicoso B. 2025. Reduced efficacy of selection on a young Z chromosome region of schistosoma japonicum. Genome Biology and Evolution. 17(2), evaf021.","chicago":"Mrnjavac, Andrea, and Beatriz Vicoso. “Reduced Efficacy of Selection on a Young Z Chromosome Region of Schistosoma Japonicum.” <i>Genome Biology and Evolution</i>. Oxford University Press, 2025. <a href=\"https://doi.org/10.1093/gbe/evaf021\">https://doi.org/10.1093/gbe/evaf021</a>.","ama":"Mrnjavac A, Vicoso B. Reduced efficacy of selection on a young Z chromosome region of schistosoma japonicum. <i>Genome Biology and Evolution</i>. 2025;17(2). doi:<a href=\"https://doi.org/10.1093/gbe/evaf021\">10.1093/gbe/evaf021</a>","ieee":"A. Mrnjavac and B. Vicoso, “Reduced efficacy of selection on a young Z chromosome region of schistosoma japonicum,” <i>Genome Biology and Evolution</i>, vol. 17, no. 2. Oxford University Press, 2025.","apa":"Mrnjavac, A., &#38; Vicoso, B. (2025). Reduced efficacy of selection on a young Z chromosome region of schistosoma japonicum. <i>Genome Biology and Evolution</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/gbe/evaf021\">https://doi.org/10.1093/gbe/evaf021</a>","mla":"Mrnjavac, Andrea, and Beatriz Vicoso. “Reduced Efficacy of Selection on a Young Z Chromosome Region of Schistosoma Japonicum.” <i>Genome Biology and Evolution</i>, vol. 17, no. 2, evaf021, Oxford University Press, 2025, doi:<a href=\"https://doi.org/10.1093/gbe/evaf021\">10.1093/gbe/evaf021</a>."},"publication_identifier":{"eissn":["1759-6653"]},"tmp":{"short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"pmid":1,"related_material":{"link":[{"url":"https://git.ista.ac.at/amrnjava/schistosomes_slower_z","relation":"software"}],"record":[{"status":"public","relation":"earlier_version","id":"18549"}]},"type":"journal_article","department":[{"_id":"BeVi"}],"date_created":"2025-03-09T23:01:27Z","doi":"10.1093/gbe/evaf021","date_updated":"2026-07-29T08:36:27Z","oa_version":"Published Version","ddc":["570"],"corr_author":"1","user_id":"317138e5-6ab7-11ef-aa6d-ffef3953e345","month":"02","abstract":[{"text":"Sex-linked and autosomal loci experience different selective pressures and evolutionary dynamics. X (or Z) chromosomes are often hemizygous in males (or females), as Y (or W) chromosomes often degenerate. Such hemizygous regions can be under greater efficacy of selection, as recessive mutations are immediately exposed to selection in the heterogametic sex leading to faster adaptation and faster divergence on the X chromosome (the so-called Faster-X or Faster-Z effect). However, in young nonrecombining regions, Y/W chromosomes often have many functional genes, and many X/Z-linked loci are therefore diploid. The sheltering of recessive mutations on the X/Z by the Y/W homolog is expected to drive slower adaptation for diploid X/Z loci, i.e. a reduction in the efficacy of selection. While the Faster-X effect has been studied extensively, much less is known empirically about the evolutionary dynamics of diploid X or Z chromosomes. Here, we took advantage of published population genomic data in the female-heterogametic human parasite Schistosoma japonicum to characterize the gene content and diversity levels of the diploid and hemizygous regions of the Z chromosome. We used different metrics of selective pressures acting on genes to test for differences in the efficacy of selection in hemizygous and diploid Z regions, relative to autosomes. We found consistent patterns suggesting reduced Ne, and reduced efficacy of purifying selection, on both hemizygous and diploid Z regions. Moreover, relaxed selection was particularly pronounced for female-biased genes on the diploid Z, as predicted by recent theoretical work.","lang":"eng"}],"language":[{"iso":"eng"}],"intvolume":"        17","status":"public","acknowledgement":"The authors would like to thank three anonymous reviewers for comments and suggestions. We are also grateful to Christelle Fraïsse, Marwan Elkrewi, and Filip Ruzicka for the help in this project.","volume":17,"publication":"Genome Biology and Evolution","article_processing_charge":"Yes","publisher":"Oxford University Press","_id":"19370","quality_controlled":"1","issue":"2","article_number":"evaf021","external_id":{"pmid":["39913672"],"isi":["001423671400001"]},"date_published":"2025-02-01T00:00:00Z","title":"Reduced efficacy of selection on a young Z chromosome region of schistosoma japonicum","author":[{"id":"353FAC84-AE61-11E9-8BFC-00D3E5697425","full_name":"Mrnjavac, Andrea","last_name":"Mrnjavac","first_name":"Andrea"},{"id":"49E1C5C6-F248-11E8-B48F-1D18A9856A87","full_name":"Vicoso, Beatriz","first_name":"Beatriz","orcid":"0000-0002-4579-8306","last_name":"Vicoso"}],"isi":1,"has_accepted_license":"1","year":"2025","publication_status":"published"},{"publisher":"Institute of Science and Technology Austria","article_processing_charge":"No","_id":"18531","keyword":["Sex chromosomes","evolution","selection","sheltering"],"alternative_title":["ISTA Thesis"],"degree_awarded":"PhD","abstract":[{"text":"Sex chromosomes and autosomes exhibit very different evolutionary dynamics.\r\nThe Y chromosome usually degenerates, leaving many X-linked loci hemizygous in\r\nmales. Since recessive X-linked mutations are always exposed to selection in males,\r\nselection is more efficient on the X chromosome than on autosomes on recessive\r\nmutations, leading to faster adaptation on the X chromosome than other genomic\r\nregions, if beneficial mutations are on average recessive (known as the Faster-X\r\neffect). In the presence of the functional, but non-recombining gametolog on the Y (as\r\nis often the case in young non-recombining regions), recessive mutations are\r\nsheltered from selection on the X chromosome. We model this scenario and show that\r\nthe efficiency of selection is reduced on diploid X loci due to sheltering by the Y\r\nchromosome. Reduced efficiency of selection leads to slower adaptation and\r\nincreased accumulation of deleterious mutations (Slower-X effect). We extended this\r\nmodel to explore the effect of sex-specific selection on degeneration of sex\r\nchromosomes, showing theoretically that male-limited genes degenerate on the X\r\nchromosome and female-biased genes degenerate on the Y chromosome. This\r\nprediction depends on the effective population size and the mutation rate, explaining\r\nthe variety of sex chromosome degeneration patterns observed in nature.\r\nTo test for direct evidence of a Slower-X (or Slower-Z) effect, we analyzed the\r\nZW sex chromosomes of the flatworm Schistosoma japonicum, which have a very\r\nyoung non-recombining region with non-degenerated W. Diploid Z-linked genes have\r\nhigher ratios of non-synonymous to synonymous polymorphisms than autosomal\r\ngenes, supporting reduced efficiency of selection on the diploid Z region. These results\r\nprovide evidence of sheltering by the W chromosome, a mechanism that could\r\ncontribute to Z (X) chromosome degeneration, and illustrate contrasting evolutionary\r\npatterns in old and young sex chromosome regions. In addition, genes with sexspecific patterns of expression show opposite patterns of selection in the young\r\n(diploid) and old (hemizygous) Z, showing the complex manner in which sex-specific selection shapes the evolutionary patterns of sex chromosomes. ","lang":"eng"}],"status":"public","language":[{"iso":"eng"}],"has_accepted_license":"1","year":"2024","publication_status":"published","date_published":"2024-11-11T00:00:00Z","OA_embargo":"6","author":[{"id":"353FAC84-AE61-11E9-8BFC-00D3E5697425","full_name":"Mrnjavac, Andrea","first_name":"Andrea","last_name":"Mrnjavac"}],"title":"Early stages of sex chromosome evolution","OA_place":"publisher","oa":1,"fulldoi":"https://doi.org/10.15479/at:ista:18531","publication_identifier":{"issn":["2663-337X"]},"citation":{"mla":"Mrnjavac, Andrea. <i>Early Stages of Sex Chromosome Evolution</i>. Institute of Science and Technology Austria, 2024, doi:<a href=\"https://doi.org/10.15479/at:ista:18531\">10.15479/at:ista:18531</a>.","ieee":"A. Mrnjavac, “Early stages of sex chromosome evolution,” Institute of Science and Technology Austria, 2024.","apa":"Mrnjavac, A. (2024). <i>Early stages of sex chromosome evolution</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:18531\">https://doi.org/10.15479/at:ista:18531</a>","ama":"Mrnjavac A. Early stages of sex chromosome evolution. 2024. doi:<a href=\"https://doi.org/10.15479/at:ista:18531\">10.15479/at:ista:18531</a>","chicago":"Mrnjavac, Andrea. “Early Stages of Sex Chromosome Evolution.” Institute of Science and Technology Austria, 2024. <a href=\"https://doi.org/10.15479/at:ista:18531\">https://doi.org/10.15479/at:ista:18531</a>.","ista":"Mrnjavac A. 2024. Early stages of sex chromosome evolution. Institute of Science and Technology Austria.","short":"A. Mrnjavac, Early Stages of Sex Chromosome Evolution, Institute of Science and Technology Austria, 2024."},"supervisor":[{"orcid":"0000-0002-4579-8306","first_name":"Beatriz","last_name":"Vicoso","id":"49E1C5C6-F248-11E8-B48F-1D18A9856A87","full_name":"Vicoso, Beatriz"}],"acknowledged_ssus":[{"_id":"ScienComp"},{"_id":"CampIT"}],"tmp":{"name":"Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)","short":"CC BY-NC-ND (4.0)","image":"/images/cc_by_nc_nd.png","legal_code_url":"https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode"},"file_date_updated":"2025-05-11T22:30:04Z","file":[{"relation":"source_file","date_updated":"2025-05-11T22:30:04Z","date_created":"2024-11-13T12:15:28Z","file_name":"AMrnjavac_thesis_library.docx","file_size":26870629,"file_id":"18551","checksum":"3e48b163c22114ef5d5371f758668289","content_type":"application/vnd.openxmlformats-officedocument.wordprocessingml.document","creator":"amrnjava","title":"Early stages of sex chromosome evolution","access_level":"closed","embargo_to":"open_access"},{"content_type":"application/pdf","creator":"amrnjava","checksum":"3ead60c1b678e7dcf018043aef3b5db2","embargo":"2025-05-11","file_size":4228766,"file_name":"AMrnjavac_thesis_library.pdf","file_id":"18552","date_updated":"2025-05-11T22:30:04Z","relation":"main_file","date_created":"2024-11-13T12:15:54Z","title":"Early stages of sex chromosome evolution","access_level":"open_access"}],"day":"11","date_created":"2024-11-11T08:40:45Z","date_updated":"2026-07-29T08:36:28Z","doi":"10.15479/at:ista:18531","oa_version":"Published Version","ddc":["576"],"user_id":"ba8df636-2132-11f1-aed0-ed93e2281fdd","corr_author":"1","month":"11","page":"181","related_material":{"record":[{"status":"public","relation":"part_of_dissertation","id":"12521"},{"id":"18549","status":"public","relation":"part_of_dissertation"}]},"type":"dissertation","department":[{"_id":"GradSch"},{"_id":"BeVi"}]},{"tmp":{"name":"Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)","short":"CC BY-NC-ND (4.0)","image":"/images/cc_by_nc_nd.png","legal_code_url":"https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode"},"external_id":{"biorxivid":["10.1101/2024.07.02.601697"]},"fulldoi":"https://doi.org/10.1101/2024.07.02.601697","citation":{"ieee":"A. Mrnjavac and B. Vicoso, “Evidence of a Slower-Z effect in Schistosoma japonicum,” <i>bioRxiv</i>. .","apa":"Mrnjavac, A., &#38; Vicoso, B. (n.d.). Evidence of a Slower-Z effect in Schistosoma japonicum. <i>bioRxiv</i>. <a href=\"https://doi.org/10.1101/2024.07.02.601697\">https://doi.org/10.1101/2024.07.02.601697</a>","mla":"Mrnjavac, Andrea, and Beatriz Vicoso. “Evidence of a Slower-Z Effect in Schistosoma Japonicum.” <i>BioRxiv</i>, doi:<a href=\"https://doi.org/10.1101/2024.07.02.601697\">10.1101/2024.07.02.601697</a>.","ama":"Mrnjavac A, Vicoso B. Evidence of a Slower-Z effect in Schistosoma japonicum. <i>bioRxiv</i>. doi:<a href=\"https://doi.org/10.1101/2024.07.02.601697\">10.1101/2024.07.02.601697</a>","chicago":"Mrnjavac, Andrea, and Beatriz Vicoso. “Evidence of a Slower-Z Effect in Schistosoma Japonicum.” <i>BioRxiv</i>, n.d. <a href=\"https://doi.org/10.1101/2024.07.02.601697\">https://doi.org/10.1101/2024.07.02.601697</a>.","ista":"Mrnjavac A, Vicoso B. Evidence of a Slower-Z effect in Schistosoma japonicum. bioRxiv, <a href=\"https://doi.org/10.1101/2024.07.02.601697\">10.1101/2024.07.02.601697</a>.","short":"A. Mrnjavac, B. Vicoso, BioRxiv (n.d.)."},"oa":1,"_id":"18549","main_file_link":[{"url":"https://doi.org/10.1101/2024.07.02.601697","open_access":"1"}],"OA_place":"repository","article_processing_charge":"No","publication":"bioRxiv","day":"04","status":"public","language":[{"iso":"eng"}],"abstract":[{"text":"Sex-linked and autosomal loci experience different selective pressures and\r\nevolutionary dynamics. X (or Z) chromosomes are often hemizygous, as Y (or W)\r\nchromosomes often degenerate. Such hemizygous regions can be under greater\r\nefficacy of selection, as recessive mutations are immediately exposed to selection in\r\nthe heterogametic sex (the so-called Faster-X or Faster-Z effect). However, in young\r\nnon-recombining regions, Y/W chromosomes often have many functional genes, and\r\nmany X/Z-linked loci are therefore diploid. The sheltering of recessive mutations on\r\nthe X/Z by the Y/W homolog is expected to drive a Slower-X (Slower-Z) effect for\r\ndiploid X/Z loci, i.e. a reduction in the efficacy of selection. While the Faster-X effect\r\nhas been studied extensively, much less is known empirically about the evolutionary\r\ndynamics of diploid X or Z chromosomes. Here, we took advantage of published\r\npopulation genomic data in the female-heterogametic human parasite Schistosoma\r\njaponicum to characterize the gene content and diversity levels of the diploid and\r\nhemizygous regions of the Z chromosome. We used different metrics of selective\r\npressures acting on genes to test for differences in the efficacy of selection in\r\nhemizygous and diploid Z regions, relative to autosomes. We found consistent\r\npatterns suggesting reduced Ne, and reduced efficacy of purifying selection, on both\r\nhemizygous and diploid Z regions. Moreover, relaxed selection was particularly\r\npronounced for female-biased genes on the diploid Z, as predicted by Slower-Z\r\ntheory.\r\n","lang":"eng"}],"publication_status":"draft","month":"07","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","corr_author":"1","year":"2024","oa_version":"Preprint","doi":"10.1101/2024.07.02.601697","date_created":"2024-11-13T09:12:08Z","date_updated":"2026-09-12T22:31:10Z","department":[{"_id":"BeVi"}],"title":"Evidence of a Slower-Z effect in Schistosoma japonicum","author":[{"first_name":"Andrea","last_name":"Mrnjavac","id":"353FAC84-AE61-11E9-8BFC-00D3E5697425","full_name":"Mrnjavac, Andrea"},{"last_name":"Vicoso","orcid":"0000-0002-4579-8306","first_name":"Beatriz","full_name":"Vicoso, Beatriz","id":"49E1C5C6-F248-11E8-B48F-1D18A9856A87"}],"type":"preprint","date_published":"2024-07-04T00:00:00Z","related_material":{"record":[{"id":"19370","relation":"later_version","status":"public"},{"status":"public","relation":"dissertation_contains","id":"18531"}]},"biorxivid":1},{"title":"Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution","author":[{"last_name":"Mrnjavac","first_name":"Andrea","full_name":"Mrnjavac, Andrea","id":"353FAC84-AE61-11E9-8BFC-00D3E5697425"},{"id":"4E6DC800-AE37-11E9-AC72-31CAE5697425","full_name":"Khudiakova, Kseniia","first_name":"Kseniia","orcid":"0000-0002-6246-1465","last_name":"Khudiakova"},{"first_name":"Nicholas H","orcid":"0000-0002-8548-5240","last_name":"Barton","full_name":"Barton, Nicholas H","id":"4880FE40-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0002-4579-8306","first_name":"Beatriz","last_name":"Vicoso","id":"49E1C5C6-F248-11E8-B48F-1D18A9856A87","full_name":"Vicoso, Beatriz"}],"date_published":"2023-02-01T00:00:00Z","publication_status":"published","year":"2023","has_accepted_license":"1","isi":1,"publication":"Evolution Letters","volume":7,"language":[{"iso":"eng"}],"acknowledgement":"We thank the Vicoso and Barton groups and ISTA Scientific Computing Unit. We also thank two anonymous reviewers for their valuable comments. This work was supported by the European Research Council under the European Union’s Horizon 2020 research and innovation program (grant agreements no. 715257 and no. 716117).","status":"public","intvolume":"         7","abstract":[{"lang":"eng","text":"Differentiated X chromosomes are expected to have higher rates of adaptive divergence than autosomes, if new beneficial mutations are recessive (the “faster-X effect”), largely because these mutations are immediately exposed to selection in males. The evolution of X chromosomes after they stop recombining in males, but before they become hemizygous, has not been well explored theoretically. We use the diffusion approximation to infer substitution rates of beneficial and deleterious mutations under such a scenario. Our results show that selection is less efficient on diploid X loci than on autosomal and hemizygous X loci under a wide range of parameters. This “slower-X” effect is stronger for genes affecting primarily (or only) male fitness, and for sexually antagonistic genes. These unusual dynamics suggest that some of the peculiar features of X chromosomes, such as the differential accumulation of genes with sex-specific functions, may start arising earlier than previously appreciated."}],"external_id":{"isi":["001021692200001"],"pmid":["37065438"]},"article_number":"qrac004","issue":"1","keyword":["Genetics","Ecology","Evolution","Behavior and Systematics"],"quality_controlled":"1","_id":"12521","article_processing_charge":"Yes (via OA deal)","publisher":"Oxford University Press","department":[{"_id":"GradSch"},{"_id":"BeVi"}],"ec_funded":1,"type":"journal_article","related_material":{"record":[{"relation":"dissertation_contains","status":"public","id":"18531"}]},"pmid":1,"project":[{"name":"Optimal Transport and Stochastic Dynamics","grant_number":"716117","_id":"256E75B8-B435-11E9-9278-68D0E5697425","call_identifier":"H2020"},{"grant_number":"715257","call_identifier":"H2020","_id":"250BDE62-B435-11E9-9278-68D0E5697425","name":"Prevalence and Influence of Sexual Antagonism on Genome Evolution"}],"month":"02","corr_author":"1","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","ddc":["570"],"oa_version":"Published Version","doi":"10.1093/evlett/qrac004","date_created":"2023-02-06T13:59:12Z","date_updated":"2026-09-12T22:31:10Z","article_type":"original","day":"01","file":[{"access_level":"open_access","success":1,"checksum":"a240a041cb9b9b7c8ba93a4706674a3f","content_type":"application/pdf","creator":"dernst","date_created":"2023-08-16T11:43:33Z","relation":"main_file","date_updated":"2023-08-16T11:43:33Z","file_name":"2023_EvLetters_Mrnjavac.pdf","file_size":2592189,"file_id":"14068"}],"file_date_updated":"2023-08-16T11:43:33Z","tmp":{"short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"publication_identifier":{"issn":["2056-3744"]},"fulldoi":"https://doi.org/10.1093/evlett/qrac004","citation":{"ista":"Mrnjavac A, Khudiakova K, Barton NH, Vicoso B. 2023. Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution. Evolution Letters. 7(1), qrac004.","chicago":"Mrnjavac, Andrea, Kseniia Khudiakova, Nicholas H Barton, and Beatriz Vicoso. “Slower-X: Reduced Efficiency of Selection in the Early Stages of X Chromosome Evolution.” <i>Evolution Letters</i>. Oxford University Press, 2023. <a href=\"https://doi.org/10.1093/evlett/qrac004\">https://doi.org/10.1093/evlett/qrac004</a>.","short":"A. Mrnjavac, K. Khudiakova, N.H. Barton, B. Vicoso, Evolution Letters 7 (2023).","ama":"Mrnjavac A, Khudiakova K, Barton NH, Vicoso B. Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution. <i>Evolution Letters</i>. 2023;7(1). doi:<a href=\"https://doi.org/10.1093/evlett/qrac004\">10.1093/evlett/qrac004</a>","apa":"Mrnjavac, A., Khudiakova, K., Barton, N. H., &#38; Vicoso, B. (2023). Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution. <i>Evolution Letters</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/evlett/qrac004\">https://doi.org/10.1093/evlett/qrac004</a>","ieee":"A. Mrnjavac, K. Khudiakova, N. H. Barton, and B. Vicoso, “Slower-X: Reduced efficiency of selection in the early stages of X chromosome evolution,” <i>Evolution Letters</i>, vol. 7, no. 1. Oxford University Press, 2023.","mla":"Mrnjavac, Andrea, et al. “Slower-X: Reduced Efficiency of Selection in the Early Stages of X Chromosome Evolution.” <i>Evolution Letters</i>, vol. 7, no. 1, qrac004, Oxford University Press, 2023, doi:<a href=\"https://doi.org/10.1093/evlett/qrac004\">10.1093/evlett/qrac004</a>."},"scopus_import":"1","oa":1},{"title":"ZW sex-chromosome evolution and contagious parthenogenesis in Artemia brine shrimp","author":[{"id":"0B46FACA-A8E1-11E9-9BD3-79D1E5697425","full_name":"Elkrewi, Marwan N","first_name":"Marwan N","orcid":"0000-0002-5328-7231","last_name":"Elkrewi"},{"first_name":"Uladzislava","last_name":"Khauratovich","full_name":"Khauratovich, Uladzislava","id":"5eba06f4-97d8-11ed-9f8f-d826ebdd9434"},{"last_name":"Toups","orcid":"0000-0002-9752-7380","first_name":"Melissa A","id":"4E099E4E-F248-11E8-B48F-1D18A9856A87","full_name":"Toups, Melissa A"},{"id":"57854184-AAE0-11E9-8D04-98D6E5697425","full_name":"Bett, Vincent K","last_name":"Bett","first_name":"Vincent K"},{"last_name":"Mrnjavac","first_name":"Andrea","id":"353FAC84-AE61-11E9-8BFC-00D3E5697425","full_name":"Mrnjavac, Andrea"},{"first_name":"Ariana","last_name":"Macon","full_name":"Macon, Ariana","id":"2A0848E2-F248-11E8-B48F-1D18A9856A87"},{"last_name":"Fraisse","orcid":"0000-0001-8441-5075","first_name":"Christelle","id":"32DF5794-F248-11E8-B48F-1D18A9856A87","full_name":"Fraisse, Christelle"},{"last_name":"Sax","first_name":"Luca","full_name":"Sax, Luca","id":"701c5602-97d8-11ed-96b5-b52773c70189"},{"id":"4C0A3874-F248-11E8-B48F-1D18A9856A87","full_name":"Huylmans, Ann K","first_name":"Ann K","orcid":"0000-0001-8871-4961","last_name":"Huylmans"},{"last_name":"Hontoria","first_name":"Francisco","full_name":"Hontoria, Francisco"},{"full_name":"Vicoso, Beatriz","id":"49E1C5C6-F248-11E8-B48F-1D18A9856A87","orcid":"0000-0002-4579-8306","first_name":"Beatriz","last_name":"Vicoso"}],"date_published":"2022-10-01T00:00:00Z","publication_status":"published","year":"2022","has_accepted_license":"1","isi":1,"publication":"Genetics","volume":222,"status":"public","acknowledgement":"This work was supported by the European Research Council under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 715257) and by the Austrian Science Foundation (FWF SFB F88-10).\r\nWe thank the Vicoso group for comments on the manuscript and the ISTA Scientific computing team and the Vienna Biocenter Sequencing facility for technical support.","language":[{"iso":"eng"}],"intvolume":"       222","abstract":[{"lang":"eng","text":"Eurasian brine shrimp (genus Artemia) have closely related sexual and asexual lineages of parthenogenetic females, which produce rare males at low frequencies. Although they are known to have ZW chromosomes, these are not well characterized, and it is unclear whether they are shared across the clade. Furthermore, the underlying genetic architecture of the transmission of asexuality, which can occur when rare males mate with closely related sexual females, is not well understood. We produced a chromosome-level assembly for the sexual Eurasian species Artemia sinica and characterized in detail the pair of sex chromosomes of this species. We combined this new assembly with short-read genomic data for the sexual species Artemia sp. Kazakhstan and several asexual lineages of Artemia parthenogenetica, allowing us to perform an in-depth characterization of sex-chromosome evolution across the genus. We identified a small differentiated region of the ZW pair that is shared by all sexual and asexual lineages, supporting the shared ancestry of the sex chromosomes. We also inferred that recombination suppression has spread to larger sections of the chromosome independently in the American and Eurasian lineages. Finally, we took advantage of a rare male, which we backcrossed to sexual females, to explore the genetic basis of asexuality. Our results suggest that parthenogenesis is likely partly controlled by a locus on the Z chromosome, highlighting the interplay between sex determination and asexuality."}],"external_id":{"isi":["000850270300001"],"pmid":["35977389"]},"article_number":"iyac123","issue":"2","keyword":["Genetics"],"quality_controlled":"1","_id":"12248","publisher":"Oxford University Press","article_processing_charge":"No","department":[{"_id":"BeVi"}],"ec_funded":1,"type":"journal_article","pmid":1,"related_material":{"record":[{"relation":"research_data","status":"public","id":"11653"},{"id":"19386","relation":"dissertation_contains","status":"public"}]},"project":[{"grant_number":"715257","call_identifier":"H2020","_id":"250BDE62-B435-11E9-9278-68D0E5697425","name":"Prevalence and Influence of Sexual Antagonism on Genome Evolution"},{"_id":"34ae1506-11ca-11ed-8bc3-c14f4c474396","grant_number":"F8810","name":"The highjacking of meiosis for asexual reproduction"}],"month":"10","user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","corr_author":"1","oa_version":"Published Version","ddc":["570"],"doi":"10.1093/genetics/iyac123","date_created":"2023-01-16T09:56:10Z","date_updated":"2026-09-12T22:30:31Z","article_type":"original","day":"01","file":[{"date_updated":"2023-01-30T08:59:58Z","relation":"main_file","date_created":"2023-01-30T08:59:58Z","file_name":"2022_Genetics_Elkrewi.pdf","file_size":1347136,"file_id":"12440","checksum":"f79ff5383e882ea3f95f3da47a78029d","content_type":"application/pdf","creator":"dernst","success":1,"access_level":"open_access"}],"file_date_updated":"2023-01-30T08:59:58Z","tmp":{"short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"fulldoi":"https://doi.org/10.1093/genetics/iyac123","citation":{"short":"M.N. Elkrewi, U. Khauratovich, M.A. Toups, V.K. Bett, A. Mrnjavac, A. Macon, C. Fraisse, L. Sax, A.K. Huylmans, F. Hontoria, B. Vicoso, Genetics 222 (2022).","chicago":"Elkrewi, Marwan N, Uladzislava Khauratovich, Melissa A Toups, Vincent K Bett, Andrea Mrnjavac, Ariana Macon, Christelle Fraisse, et al. “ZW Sex-Chromosome Evolution and Contagious Parthenogenesis in Artemia Brine Shrimp.” <i>Genetics</i>. Oxford University Press, 2022. <a href=\"https://doi.org/10.1093/genetics/iyac123\">https://doi.org/10.1093/genetics/iyac123</a>.","ista":"Elkrewi MN, Khauratovich U, Toups MA, Bett VK, Mrnjavac A, Macon A, Fraisse C, Sax L, Huylmans AK, Hontoria F, Vicoso B. 2022. ZW sex-chromosome evolution and contagious parthenogenesis in Artemia brine shrimp. Genetics. 222(2), iyac123.","ieee":"M. N. Elkrewi <i>et al.</i>, “ZW sex-chromosome evolution and contagious parthenogenesis in Artemia brine shrimp,” <i>Genetics</i>, vol. 222, no. 2. Oxford University Press, 2022.","mla":"Elkrewi, Marwan N., et al. “ZW Sex-Chromosome Evolution and Contagious Parthenogenesis in Artemia Brine Shrimp.” <i>Genetics</i>, vol. 222, no. 2, iyac123, Oxford University Press, 2022, doi:<a href=\"https://doi.org/10.1093/genetics/iyac123\">10.1093/genetics/iyac123</a>.","apa":"Elkrewi, M. N., Khauratovich, U., Toups, M. A., Bett, V. K., Mrnjavac, A., Macon, A., … Vicoso, B. (2022). ZW sex-chromosome evolution and contagious parthenogenesis in Artemia brine shrimp. <i>Genetics</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/genetics/iyac123\">https://doi.org/10.1093/genetics/iyac123</a>","ama":"Elkrewi MN, Khauratovich U, Toups MA, et al. ZW sex-chromosome evolution and contagious parthenogenesis in Artemia brine shrimp. <i>Genetics</i>. 2022;222(2). doi:<a href=\"https://doi.org/10.1093/genetics/iyac123\">10.1093/genetics/iyac123</a>"},"publication_identifier":{"issn":["1943-2631"]},"acknowledged_ssus":[{"_id":"ScienComp"}],"scopus_import":"1","oa":1}]