--- OA_place: publisher OA_type: hybrid PlanS_conform: '1' _id: '20330' abstract: - lang: eng text: The evolution of sexual dimorphism (the difference in average trait values between females and males, SD), is often thought to be constrained by shared genetic architecture between the sexes. Indeed, it is commonly expected that SD should negatively correlate with the intersex correlation (the genetic correlation between effects of segregating variants in females and males, r fm), either because (1) traits with ancestrally low r fm are less constrained in their ability to respond to sex-specific selection and thus evolve to be more dimorphic, or because (2) sex-specific selection, driving sexual dimorphism evolution, also acts to reduce r fm. Despite the intuitive appeal and prominence of these ideas, their generality and the conditions in which they hold remain unclear. Here, we develop models incorporating sex-specific stabilizing selection, mutation and genetic drift to examine the relationship between r fm and SD. We show that the two commonly-discussed mechanisms with the potential to generate a negative correlation between SD and r fm could just as easily generate a positive association, since the standard line of reasoning hinges on a hidden assumption that sex-specific adaptation more frequently favors increased dimorphism than reduced dimorphism. Our results provide, to our knowledge, the first mechanistic framework for understanding the conditions under which a correlation between r fm and SD may arise and offer a compelling explanation for inconsistent empirical evidence. We also make the intriguing observation that—even when selection between the two sexes is identical—drift generates nonzero SD. We quantify this effect and discuss its significance. acknowledgement: We thank Tim Connallon for useful discussions and correspondence, Himani Sachdeva and Nick Barton for comments on the manuscript and the Scientific Computing unit at ISTA for technical support. GP is the recipient of a DOC Fellowship of the Austrian Academy of Sciences at the Institute of Science and Technology Austria (DOC 25817) and received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant (agreement no. 665385). LH received funding from the European Research Council, under the HaplotypeStructure Grant (grant no. 101055327) to Nick Barton. article_number: iyaf175 article_processing_charge: Yes (via OA deal) article_type: original author: - first_name: Gemma full_name: Puixeu Sala, Gemma id: 33AB266C-F248-11E8-B48F-1D18A9856A87 last_name: Puixeu Sala orcid: 0000-0001-8330-1754 - first_name: Laura full_name: Hayward, Laura id: fc885ee5-24bf-11eb-ad7b-bcc5104c0c1b last_name: Hayward citation: ama: 'Puixeu Sala G, Hayward L. The relationship between sexual dimorphism and intersex correlation: Do models support intuition? Genetics. 2025;231(3). doi:10.1093/genetics/iyaf175' apa: 'Puixeu Sala, G., & Hayward, L. (2025). The relationship between sexual dimorphism and intersex correlation: Do models support intuition? Genetics. Oxford University Press. https://doi.org/10.1093/genetics/iyaf175' chicago: 'Puixeu Sala, Gemma, and Laura Hayward. “The Relationship between Sexual Dimorphism and Intersex Correlation: Do Models Support Intuition?” Genetics. Oxford University Press, 2025. https://doi.org/10.1093/genetics/iyaf175.' ieee: 'G. Puixeu Sala and L. Hayward, “The relationship between sexual dimorphism and intersex correlation: Do models support intuition?,” Genetics, vol. 231, no. 3. Oxford University Press, 2025.' ista: 'Puixeu Sala G, Hayward L. 2025. The relationship between sexual dimorphism and intersex correlation: Do models support intuition? Genetics. 231(3), iyaf175.' mla: 'Puixeu Sala, Gemma, and Laura Hayward. “The Relationship between Sexual Dimorphism and Intersex Correlation: Do Models Support Intuition?” Genetics, vol. 231, no. 3, iyaf175, Oxford University Press, 2025, doi:10.1093/genetics/iyaf175.' short: G. Puixeu Sala, L. Hayward, Genetics 231 (2025). corr_author: '1' date_created: 2025-09-10T05:48:04Z date_published: 2025-11-01T00:00:00Z date_updated: 2026-01-05T13:04:07Z day: '01' ddc: - '570' department: - _id: BeVi - _id: NiBa doi: 10.1093/genetics/iyaf175 ec_funded: 1 external_id: isi: - '001598595000001' file: - access_level: open_access checksum: bbb73bbf8617812d4d8db4af92be9538 content_type: application/pdf creator: dernst date_created: 2026-01-05T13:03:18Z date_updated: 2026-01-05T13:03:18Z file_id: '20946' file_name: 2025_Genetics_Puixeu.pdf file_size: 1550562 relation: main_file success: 1 file_date_updated: 2026-01-05T13:03:18Z has_accepted_license: '1' intvolume: ' 231' isi: 1 issue: '3' language: - iso: eng month: '11' oa: 1 oa_version: Published Version project: - _id: 9B9DFC9E-BA93-11EA-9121-9846C619BF3A grant_number: '25817' name: 'Sexual conflict: resolution, constraints and biomedical implications' - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program - _id: bd6958e0-d553-11ed-ba76-86eba6a76c00 grant_number: '101055327' name: Understanding the evolution of continuous genomes publication: Genetics publication_identifier: issn: - 1943-2631 publication_status: published publisher: Oxford University Press quality_controlled: '1' scopus_import: '1' status: public title: 'The relationship between sexual dimorphism and intersex correlation: Do models support intuition?' tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 231 year: '2025' ... --- OA_place: publisher _id: '14058' abstract: - lang: eng text: "Females and males across species are subject to divergent selective pressures arising\r\nfrom di↵erent reproductive interests and ecological niches. This often translates into a\r\nintricate array of sex-specific natural and sexual selection on traits that have a shared\r\ngenetic basis between both sexes, causing a genetic sexual conflict. The resolution of\r\nthis conflict mostly relies on the evolution of sex-specific expression of the shared genes,\r\nleading to phenotypic sexual dimorphism. Such sex-specific gene expression is thought\r\nto evolve via modifications of the genetic networks ultimately linked to sex-determining\r\ntranscription factors. Although much empirical and theoretical evidence supports this\r\nstandard picture of the molecular basis of sexual conflict resolution, there still are a\r\nfew open questions regarding the complex array of selective forces driving phenotypic\r\ndi↵erentiation between the sexes, as well as the molecular mechanisms underlying sexspecific adaptation. I address some of these open questions in my PhD thesis.\r\nFirst, how do patterns of phenotypic sexual dimorphism vary within populations,\r\nas a response to the temporal and spatial changes in sex-specific selective forces? To\r\ntackle this question, I analyze the patterns of sex-specific phenotypic variation along\r\nthree life stages and across populations spanning the whole geographical range of Rumex\r\nhastatulus, a wind-pollinated angiosperm, in the first Chapter of the thesis.\r\nSecond, how do gene expression patterns lead to phenotypic dimorphism, and what\r\nare the molecular mechanisms underlying the observed transcriptomic variation? I\r\naddress this question by examining the sex- and tissue-specific expression variation in\r\nnewly-generated datasets of sex-specific expression in heads and gonads of Drosophila\r\nmelanogaster. I additionally used two complementary approaches for the study of the\r\ngenetic basis of sex di↵erences in gene expression in the second and third Chapters of\r\nthe thesis.\r\nThird, how does intersex correlation, thought to be one of the main aspects constraining the ability for the two sexes to decouple, interact with the evolution of sexual\r\ndimorphism? I develop models of sex-specific stabilizing selection, mutation and drift\r\nto formalize common intuition regarding the patterns of covariation between intersex\r\ncorrelation and sexual dimorphism in the fourth Chapter of the thesis.\r\nAlltogether, the work described in this PhD thesis provides useful insights into the\r\nlinks between genetic, transcriptomic and phenotypic layers of sex-specific variation,\r\nand contributes to our general understanding of the dynamics of sexual dimorphism\r\nevolution." alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Gemma full_name: Puixeu Sala, Gemma id: 33AB266C-F248-11E8-B48F-1D18A9856A87 last_name: Puixeu Sala orcid: 0000-0001-8330-1754 citation: ama: 'Puixeu Sala G. The molecular basis of sexual dimorphism: Experimental and theoretical characterization of phenotypic, transcriptomic and genetic patterns of sex-specific adaptation. 2023. doi:10.15479/at:ista:14058' apa: 'Puixeu Sala, G. (2023). The molecular basis of sexual dimorphism: Experimental and theoretical characterization of phenotypic, transcriptomic and genetic patterns of sex-specific adaptation. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14058' chicago: 'Puixeu Sala, Gemma. “The Molecular Basis of Sexual Dimorphism: Experimental and Theoretical Characterization of Phenotypic, Transcriptomic and Genetic Patterns of Sex-Specific Adaptation.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14058.' ieee: 'G. Puixeu Sala, “The molecular basis of sexual dimorphism: Experimental and theoretical characterization of phenotypic, transcriptomic and genetic patterns of sex-specific adaptation,” Institute of Science and Technology Austria, 2023.' ista: 'Puixeu Sala G. 2023. The molecular basis of sexual dimorphism: Experimental and theoretical characterization of phenotypic, transcriptomic and genetic patterns of sex-specific adaptation. Institute of Science and Technology Austria.' mla: 'Puixeu Sala, Gemma. The Molecular Basis of Sexual Dimorphism: Experimental and Theoretical Characterization of Phenotypic, Transcriptomic and Genetic Patterns of Sex-Specific Adaptation. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14058.' short: 'G. Puixeu Sala, The Molecular Basis of Sexual Dimorphism: Experimental and Theoretical Characterization of Phenotypic, Transcriptomic and Genetic Patterns of Sex-Specific Adaptation, Institute of Science and Technology Austria, 2023.' corr_author: '1' date_created: 2023-08-15T10:20:40Z date_published: 2023-08-15T00:00:00Z date_updated: 2026-04-07T13:25:34Z day: '15' ddc: - '576' degree_awarded: PhD department: - _id: GradSch - _id: NiBa - _id: BeVi doi: 10.15479/at:ista:14058 ec_funded: 1 file: - access_level: closed checksum: 4e44e169f2724ee8c9324cd60bcc2b71 content_type: application/zip creator: gpuixeus date_created: 2023-08-16T18:15:17Z date_updated: 2023-08-17T06:55:24Z file_id: '14075' file_name: Thesis_latex_forpdfa.zip file_size: 10891454 relation: source_file - access_level: open_access checksum: e10b04cd8f3fecc0d9ef6e6868b6e1e8 content_type: application/pdf creator: gpuixeus date_created: 2023-08-18T10:47:55Z date_updated: 2023-08-18T10:47:55Z file_id: '14079' file_name: PhDThesis_PuixeuG.pdf file_size: 19856686 relation: main_file success: 1 file_date_updated: 2023-08-18T10:47:55Z has_accepted_license: '1' language: - iso: eng month: '08' oa: 1 oa_version: Published Version page: '230' project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program - _id: 9B9DFC9E-BA93-11EA-9121-9846C619BF3A grant_number: '25817' name: 'Sexual conflict: resolution, constraints and biomedical implications' publication_identifier: isbn: - 978-3-99078-035-0 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '9803' relation: research_data status: public - id: '12933' relation: research_data status: public - id: '6831' relation: part_of_dissertation status: public - id: '14077' relation: part_of_dissertation status: public status: public supervisor: - first_name: Beatriz full_name: Vicoso, Beatriz id: 49E1C5C6-F248-11E8-B48F-1D18A9856A87 last_name: Vicoso orcid: 0000-0002-4579-8306 - first_name: Nicholas H full_name: Barton, Nicholas H id: 4880FE40-F248-11E8-B48F-1D18A9856A87 last_name: Barton orcid: 0000-0002-8548-5240 title: 'The molecular basis of sexual dimorphism: Experimental and theoretical characterization of phenotypic, transcriptomic and genetic patterns of sex-specific adaptation' tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- _id: '14077' abstract: - lang: eng text: "The regulatory architecture of gene expression is known to differ substantially between sexes in Drosophila, but most studies performed\r\nso far used whole-body data and only single crosses, which may have limited their scope to detect patterns that are robust across tissues\r\nand biological replicates. Here, we use allele-specific gene expression of parental and reciprocal hybrid crosses between 6 Drosophila\r\nmelanogaster inbred lines to quantify cis- and trans-regulatory variation in heads and gonads of both sexes separately across 3 replicate\r\ncrosses. Our results suggest that female and male heads, as well as ovaries, have a similar regulatory architecture. On the other hand,\r\ntestes display more and substantially different cis-regulatory effects, suggesting that sex differences in the regulatory architecture that\r\nhave been previously observed may largely derive from testis-specific effects. We also examine the difference in cis-regulatory variation\r\nof genes across different levels of sex bias in gonads and heads. Consistent with the idea that intersex correlations constrain expression\r\nand can lead to sexual antagonism, we find more cis variation in unbiased and moderately biased genes in heads. In ovaries, reduced cis\r\nvariation is observed for male-biased genes, suggesting that cis variants acting on these genes in males do not lead to changes in ovary\r\nexpression. Finally, we examine the dominance patterns of gene expression and find that sex- and tissue-specific patterns of inheritance\r\nas well as trans-regulatory variation are highly variable across biological crosses, although these were performed in highly controlled\r\nexperimental conditions. This highlights the importance of using various genetic backgrounds to infer generalizable patterns." acknowledged_ssus: - _id: ScienComp acknowledgement: We thank members of the Vicoso Group for comments on the manuscript, the Scientific Computing Unit at ISTA for technical support, and 2 anonymous reviewers for useful feedback. GP is the recipient of a DOC Fellowship of the Austrian Academy of Sciences at the Institute of Science and Technology Austria (DOC 25817) and received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant (agreement no. 665385). article_processing_charge: Yes article_type: original author: - first_name: Gemma full_name: Puixeu Sala, Gemma id: 33AB266C-F248-11E8-B48F-1D18A9856A87 last_name: Puixeu Sala orcid: 0000-0001-8330-1754 - first_name: Ariana full_name: Macon, Ariana id: 2A0848E2-F248-11E8-B48F-1D18A9856A87 last_name: Macon - first_name: Beatriz full_name: Vicoso, Beatriz id: 49E1C5C6-F248-11E8-B48F-1D18A9856A87 last_name: Vicoso orcid: 0000-0002-4579-8306 citation: ama: 'Puixeu Sala G, Macon A, Vicoso B. Sex-specific estimation of cis and trans regulation of gene expression in heads and gonads of Drosophila melanogaster. G3: Genes, Genomes, Genetics. 2023;13(8). doi:10.1093/g3journal/jkad121' apa: 'Puixeu Sala, G., Macon, A., & Vicoso, B. (2023). Sex-specific estimation of cis and trans regulation of gene expression in heads and gonads of Drosophila melanogaster. G3: Genes, Genomes, Genetics. Oxford University Press. https://doi.org/10.1093/g3journal/jkad121' chicago: 'Puixeu Sala, Gemma, Ariana Macon, and Beatriz Vicoso. “Sex-Specific Estimation of Cis and Trans Regulation of Gene Expression in Heads and Gonads of Drosophila Melanogaster.” G3: Genes, Genomes, Genetics. Oxford University Press, 2023. https://doi.org/10.1093/g3journal/jkad121.' ieee: 'G. Puixeu Sala, A. Macon, and B. Vicoso, “Sex-specific estimation of cis and trans regulation of gene expression in heads and gonads of Drosophila melanogaster,” G3: Genes, Genomes, Genetics, vol. 13, no. 8. Oxford University Press, 2023.' ista: 'Puixeu Sala G, Macon A, Vicoso B. 2023. Sex-specific estimation of cis and trans regulation of gene expression in heads and gonads of Drosophila melanogaster. G3: Genes, Genomes, Genetics. 13(8).' mla: 'Puixeu Sala, Gemma, et al. “Sex-Specific Estimation of Cis and Trans Regulation of Gene Expression in Heads and Gonads of Drosophila Melanogaster.” G3: Genes, Genomes, Genetics, vol. 13, no. 8, Oxford University Press, 2023, doi:10.1093/g3journal/jkad121.' short: 'G. Puixeu Sala, A. Macon, B. Vicoso, G3: Genes, Genomes, Genetics 13 (2023).' corr_author: '1' date_created: 2023-08-18T06:52:14Z date_published: 2023-08-01T00:00:00Z date_updated: 2026-04-07T13:25:34Z day: '01' ddc: - '570' department: - _id: BeVi - _id: NiBa - _id: GradSch doi: 10.1093/g3journal/jkad121 ec_funded: 1 external_id: isi: - '001002997200001' pmid: - '37259621' file: - access_level: open_access checksum: c62e29fc7c5efbf8356f4c60cab4a2d1 content_type: application/pdf creator: dernst date_created: 2023-11-07T09:00:19Z date_updated: 2023-11-07T09:00:19Z file_id: '14498' file_name: 2023_G3_Puixeu.pdf file_size: 845642 relation: main_file success: 1 file_date_updated: 2023-11-07T09:00:19Z has_accepted_license: '1' intvolume: ' 13' isi: 1 issue: '8' keyword: - Genetics (clinical) - Genetics - Molecular Biology language: - iso: eng month: '08' oa: 1 oa_version: Published Version pmid: 1 project: - _id: 2564DBCA-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '665385' name: International IST Doctoral Program - _id: 9B9DFC9E-BA93-11EA-9121-9846C619BF3A grant_number: '25817' name: 'Sexual conflict: resolution, constraints and biomedical implications' publication: 'G3: Genes, Genomes, Genetics' publication_identifier: issn: - 2160-1836 publication_status: published publisher: Oxford University Press quality_controlled: '1' related_material: record: - id: '12933' relation: research_data status: public - id: '14058' relation: dissertation_contains status: public scopus_import: '1' status: public title: Sex-specific estimation of cis and trans regulation of gene expression in heads and gonads of Drosophila melanogaster tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 13 year: '2023' ...