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Fořt J, Flegr J, Kuba R, Kaňková Š. Fertility of Czech Gay and Straight Men, Women, and Their Relatives: Testing the Sexually Antagonistic Gene Hypothesis. ARCHIVES OF SEXUAL BEHAVIOR 2024; 53:1747-1761. [PMID: 38472605 PMCID: PMC11106150 DOI: 10.1007/s10508-024-02827-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 03/14/2024]
Abstract
One proposal for the persistence of homosexuality in the human population is the sexually antagonistic gene hypothesis, which suggests that the lower fertility of homosexual individuals, especially men, may be compensated by higher fertility of their relatives of the opposite sex. To test this hypothesis, we have collected data from 7,312 heterosexual men, 459 gay men, 3,352 heterosexual women, and 79 lesbian women mainly from Czechia. In an online survey, participants answered questions regarding their own as well as their parents' and grandparents' fertility. For men, we obtained no significant results except for higher fertility of gay men's paternal grandmothers, but the magnitude of this effect was very small. For the female sample, we recorded lower fertility of lesbian women's mothers and fathers. In line with our expectations, both gay men and lesbian women had lower fertility rates than their heterosexual counterparts. Our results are consistent with recent studies which likewise do not support the sexually antagonistic gene hypothesis.
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Affiliation(s)
- Jakub Fořt
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, 128 00, Prague, Czechia.
| | - Jaroslav Flegr
- Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague, Czechia
| | - Radim Kuba
- Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague, Czechia
- Department of Biology Education, Faculty of Science, Charles University, Prague, Czechia
| | - Šárka Kaňková
- Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague, Czechia
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2
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Zahran A, Skorska MN, Coome LA, VanderLaan DP. Recalled Childhood Separation Anxiety in Relation to Sex, Sexual Orientation, and Gender Identity in Thailand. JOURNAL OF SEX RESEARCH 2023:1-11. [PMID: 38016032 DOI: 10.1080/00224499.2023.2279238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
Same-sex sexual attraction is an evolutionary paradox. It is influenced by genes but also associated with reduced reproduction. An altruistic disposition toward kin could increase relatives' reproduction, thus addressing this paradox. Developmentally, such a disposition may manifest as anxiety during separation from kin. This hypothesis has been supported among androphilic (i.e. sexually attracted to males) males, but few similar studies of gynephilic (i.e. sexually attracted to females) females exist. We examined recalled childhood separation anxiety in Thailand and employed the largest and most sexually and gender-diverse sample to date (N = 1403). Among heterosexuals, men recalled less concern for parents' and siblings' well-being during separation than women. Androphilic males evidenced elevated concern for parents' and siblings' well-being during separation, and transfeminine androphilic males known as sao praphet song reported heightened anxiety when separated from parents. Among females, transmasculine gynephilic females known as toms recalled less concern about parents' well-being during separation than feminine females who are attracted to toms and known as dees. Bisexual women recalled less anxiety when separated from parents than dees and lesbian and heterosexual women. These findings suggest a disposition toward heightened kin-directed altruism is evident in childhood among androphilic males, but not gynephilic females.
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Affiliation(s)
- Adhm Zahran
- Department of Psychology, Toronto Metropolitan University
- Department of Psychology, University of Toronto Mississauga
| | - Malvina N Skorska
- Department of Psychology, University of Toronto Mississauga
- Child and Youth Psychiatry, Centre for Addiction and Mental Health
| | | | - Doug P VanderLaan
- Department of Psychology, University of Toronto Mississauga
- Child and Youth Psychiatry, Centre for Addiction and Mental Health
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3
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Balthazart J, Roselli CE. Hormonal, Genetic, Immunological: An Array of Mechanisms but How Do They Interact, If at All? ARCHIVES OF SEXUAL BEHAVIOR 2023; 52:2963-2971. [PMID: 36376746 DOI: 10.1007/s10508-022-02469-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 10/28/2022] [Accepted: 10/30/2022] [Indexed: 05/20/2023]
Affiliation(s)
| | - Charles E Roselli
- Department of Chemical, Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, USA
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4
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VanderLaan DP, Skorska MN, Peragine DE, Coome LA. Carving the Biodevelopment of Same-Sex Sexual Orientation at Its Joints. ARCHIVES OF SEXUAL BEHAVIOR 2023; 52:2939-2962. [PMID: 35960401 DOI: 10.1007/s10508-022-02360-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/30/2022] [Accepted: 06/04/2022] [Indexed: 06/15/2023]
Abstract
Sexual orientation is a core aspect of human experience and understanding its development is fundamental to psychology as a scientific discipline. Biological perspectives have played an important role in uncovering the processes that contribute to sexual orientation development. Research in this field has relied on a variety of populations, including community, clinical, and cross-cultural samples, and has commonly focused on female gynephilia (i.e., female sexual attraction to adult females) and male androphilia (i.e., male sexual attraction to adult males). Genetic, hormonal, and immunological processes all appear to influence sexual orientation. Consistent with biological perspectives, there are sexual orientation differences in brain development and evidence indicates that similar biological influences apply across cultures. An outstanding question in the field is whether the hypothesized biological influences are all part of the same process or represent different developmental pathways leading to same-sex sexual orientation. Some studies indicate that same-sex sexually oriented people can be divided into subgroups who likely experienced different biological influences. Consideration of gender expression in addition to sexual orientation might help delineate such subgroups. Thus, future research on the possible existence of such subgroups could prove to be valuable for uncovering the biological development of sexual orientation. Recommendations for such future research are discussed.
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Affiliation(s)
- Doug P VanderLaan
- Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada.
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada.
| | - Malvina N Skorska
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Diana E Peragine
- Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
| | - Lindsay A Coome
- Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON, L5L 1C6, Canada
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5
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Bragazzi NL, Converti M, Crapanzano A, Zerbetto R, Siri A, Khamisy-Farah R. Probing the genomic landscape of human sexuality: a critical systematic review of the literature. Front Genet 2023; 14:1184758. [PMID: 37693319 PMCID: PMC10483070 DOI: 10.3389/fgene.2023.1184758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 07/31/2023] [Indexed: 09/12/2023] Open
Abstract
Whether human sexuality is the result of nature or nurture (or their complex interplay) represents a hot, often ideologically driven, and highly polarized debate with political and social ramifications, and with varying, conflicting findings reported in the literature. A number of heritability and behavioral genetics studies, including pedigree-based investigations, have hypothesized inheritance patterns of human sexual behaviors. On the other hand, in most twin, adoption, and nuclear family studies, it was not possible to disentangle between underlying genetic and shared environmental sources. Furthermore, these studies were not able to estimate the precise extent of genetic loading and to shed light both on the number and nature of the putative inherited factors, which remained largely unknown. Molecular genetic studies offer an unprecedented opportunity to overcome these drawbacks, by dissecting the molecular basis of human sexuality and allowing a better understanding of its biological roots if any. However, there exists no systematic review of the molecular genetics of human sexuality. Therefore, we undertook this critical systematic review and appraisal of the literature, with the ambitious aims of filling in these gaps of knowledge, especially from the methodological standpoint, and providing guidance to future studies. Sixteen studies were finally retained and overviewed in the present systematic review study. Seven studies were linkage studies, four studies utilized the candidate gene approach, and five studies were GWAS investigations. Limitations of these studies and implications for further research are discussed.
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Affiliation(s)
- Nicola Luigi Bragazzi
- Laboratory for Industrial and Applied Mathematics (LIAM), Department of Mathematics and Statistics, York University, Toronto, ON, Canada
- Postgraduate School of Public Health, Department of Health Sciences (DISSAL), University of Genoa, Genoa, Italy
- United Nations Educational, Scientific and Cultural Organization (UNESCO) Chair, Health Anthropology Biosphere and Healing Systems, University of Genoa, Genoa, Italy
| | | | - Andrea Crapanzano
- Department of Counseling, San Francisco State University, San Francisco, CA, United States
| | | | - Anna Siri
- United Nations Educational, Scientific and Cultural Organization (UNESCO) Chair, Health Anthropology Biosphere and Healing Systems, University of Genoa, Genoa, Italy
| | - Rola Khamisy-Farah
- Clalit Health Services, Akko, Israel
- Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
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6
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Johnson L, Lukert B. Science, Scripture, and Sexuality: The US United Methodist Church at Crossroads. JOURNAL OF RELIGION AND HEALTH 2023:10.1007/s10943-023-01806-7. [PMID: 37079172 PMCID: PMC10117265 DOI: 10.1007/s10943-023-01806-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/21/2023] [Indexed: 05/03/2023]
Abstract
During the past 50 years, medical and behavioral scientists have made great progress in understanding the variables which influence the development of sexual orientation, identity, and consequent behavior. In most instances, homosexuality is influenced by hormonal, genetic, and immunologic variables during fetal development, and the effects cannot usually be altered without consequence. The recent struggle within The United Methodist Church in the USA reflects the difficulty that society in general has with accepting homosexuality as part of the spectrum of sexuality. Hopefully, understanding the factors influencing sexual orientation will aid in reducing prejudice and eventually bring an end to the pain endured by the LGBTQ community, and the conflict within The United Methodist Church, a prototype of the struggle.
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Clemens B, Lefort-Besnard J, Ritter C, Smith E, Votinov M, Derntl B, Habel U, Bzdok D. Accurate machine learning prediction of sexual orientation based on brain morphology and intrinsic functional connectivity. Cereb Cortex 2023; 33:4013-4025. [PMID: 36104854 PMCID: PMC10068286 DOI: 10.1093/cercor/bhac323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 07/20/2022] [Accepted: 07/21/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Sexual orientation in humans represents a multilevel construct that is grounded in both neurobiological and environmental factors. OBJECTIVE Here, we bring to bear a machine learning approach to predict sexual orientation from gray matter volumes (GMVs) or resting-state functional connectivity (RSFC) in a cohort of 45 heterosexual and 41 homosexual participants. METHODS In both brain assessments, we used penalized logistic regression models and nonparametric permutation. RESULTS We found an average accuracy of 62% (±6.72) for predicting sexual orientation based on GMV and an average predictive accuracy of 92% (±9.89) using RSFC. Regions in the precentral gyrus, precuneus and the prefrontal cortex were significantly informative for distinguishing heterosexual from homosexual participants in both the GMV and RSFC settings. CONCLUSIONS These results indicate that, aside from self-reports, RSFC offers neurobiological information valuable for highly accurate prediction of sexual orientation. We demonstrate for the first time that sexual orientation is reflected in specific patterns of RSFC, which enable personalized, brain-based predictions of this highly complex human trait. While these results are preliminary, our neurobiologically based prediction framework illustrates the great value and potential of RSFC for revealing biologically meaningful and generalizable predictive patterns in the human brain.
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Affiliation(s)
- Benjamin Clemens
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
- Research Center Jülich, Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Strase, 52428 Jülich, Germany
| | | | - Christoph Ritter
- Interdisciplinary Center for Clinical Research (IZKF), RWTH Aachen University, Pauwelsstr. 30, 52074 Aachen, Germany
| | - Elke Smith
- Biological Psychology, Department of Psychology, University of Cologne, Bernhard-Feilchenfeld-Str. 11, 50969 Cologne, Germany
| | - Mikhail Votinov
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
- Research Center Jülich, Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Strase, 52428 Jülich, Germany
| | - Birgit Derntl
- Department of Psychiatry and Psychotherapy, University of Tübingen, Calwerst. 14, 72076 Tübingen, Germany
- Werner Reichardt Center for Integrative Neuroscience (CIN), University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany
| | - Ute Habel
- Department of Psychiatry, Psychotherapy and Psychosomatics, Faculty of Medicine, RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
- Research Center Jülich, Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10), Wilhelm-Johnen-Strase, 52428 Jülich, Germany
| | - Danilo Bzdok
- McConnell Brain Imaging Centre, McGill University, 3801 University Rue, Montreal Quebec H3A 2B4, Canada
- Department of Biomedical Engineering, McGill University, 3775 University Rue, Montreal Quebec H3A 2B4, Canada
- Faculty of Medicine, Montreal Neurological Institute (MNI) and Hospital, McGill University, 3801 University Rue, Montreal Quebec H3A 2B4, Canada
- Mila–Quebec Artificial Intelligence Institute, 6666 Rue St-Urbain #200, Montreal Quebec H2S 3H1, Canada
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Tasos E. To What Extent are Prenatal Androgens Involved in the Development of Male Homosexuality in Humans? JOURNAL OF HOMOSEXUALITY 2022; 69:1928-1963. [PMID: 34080960 DOI: 10.1080/00918369.2021.1933792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Endocrine variations, including possibly reduced exposure to androgens, may contribute to the development of male homosexuality, with animal models demonstrating same-sex mate preference with altered exposure during prenatal or early postnatal development. As similar studies in humans are impossible, indirect physical and cognitive measures of androgen exposure are used. Some studies suggest that physical measures affected by prenatal androgens, including the index-to-ring finger ratio, growth indices, and facial structure, are more "feminine" in gay men. Gay men also exhibit significant childhood gender non-conformity and a "feminized" anatomical and functional brain pattern in sexual arousal, as well as domains such as language, visuospatial skills and hemispheric relationships. However, many of these results are equivocal and may be confounded by other factors. Research has also been hampered by inconsistencies in the reporting of sexual orientation and the potentially unrepresentative populations of gay men studied, while additional complexities pertaining to gender conformity and sexual role may also influence results.
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Affiliation(s)
- Emmanouil Tasos
- School of Clinical Medicine, University of Cambridge, Cambridge, UK
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9
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Semenyna SW, Gómez Jiménez FR, Vasey PL. Confounds, Causality, and Sexual Orientation: The Implications of a Population-Level Study of Sibling Characteristics and Same-Sex Attraction. JOURNAL OF SEX RESEARCH 2022; 59:690-696. [PMID: 35040379 DOI: 10.1080/00224499.2021.1990199] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Representative samples, and especially population samples, are coveted sources of high-quality data in psychological science. In their recent article, Ablaza et al. (2021) used a population sample of marriages and registered partnerships in the Netherlands to examine the relationships between sibling characteristics and sexual orientation. We discuss the implications of this work for understanding the fraternal and sororal birth order effects on male and female same-sex attraction, and how both relate to maternal reproduction. The causal assumptions of these findings are explored, as well as the necessity of population-level data, and whether the data presented by Ablaza et al. are truly representative of the Dutch population.
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Affiliation(s)
| | | | - Paul L Vasey
- Department of Psychology, University of Lethbridge
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10
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Rinaldi A. I was born this way: New research confirms that a mix of prenatal factors and genetic differences could explain human sexual orientation: New research confirms that a mix of prenatal factors and genetic differences could explain human sexual orientation. EMBO Rep 2022; 23:e55290. [PMID: 35575021 PMCID: PMC9171406 DOI: 10.15252/embr.202255290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 11/09/2022] Open
Abstract
Homosexuality has been a constant throughout human evolution and civilization, and yet, science has been slow to look at the causes of sexual preferences.
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11
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Jain S, Rana M. Alternative Sexual Orientation in Humans: What Is Known and What Needs to Be Known Further. JOURNAL OF HOMOSEXUALITY 2022; 69:1004-1029. [PMID: 33788667 DOI: 10.1080/00918369.2021.1898805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Since the 20th century, multiple studies have linked the variations in human sexual orientation, from heterosexuality to bisexuality or homosexuality, to a wide range of biological factors. However, a clear mechanism that leads to the development of these variations has not been established yet. This review consolidates various comprehensive studies on the possible biological factors in the fields of genetics, epigenetics, uterine environment, hormones, neuroanatomy, and neurobiology that lead to these variations. One intriguing question that 'homosexuality phenotype' faces is its ability to avoid elimination by Darwinian selection. This review tries to explain why natural selection is not eliminating the genetic factors associated with homosexuality even at the cost of the evolutionary fitness of homosexual individuals. Studies supporting certain strong candidates for alternative sexual orientation (ASO) are highlighted, which can become new research avenues for investigators in this field. Further, a novel speculation is proposed that might be contributing to the development of variation in human sexuality.
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Affiliation(s)
- Sidhant Jain
- Department of Zoology, University of Delhi, Delhi, India
| | - Meenakshi Rana
- Department of Zoology, University of Delhi, Delhi, India
- Dyal Singh College, University of Delhi, Delhi, India
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12
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Swift-Gallant A, Coome LA, Monks DA, VanderLaan DP. Recalled Childhood Separation Anxiety Differs by Anal Sex Role among Gay Men. JOURNAL OF SEX RESEARCH 2022; 59:546-554. [PMID: 33821703 DOI: 10.1080/00224499.2021.1903378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Male androphilia (i.e., male sexual attraction to adult males) is considered an evolutionary paradox because it is partially influenced by genes and associated with decreased reproduction. Traits associated with attachment to genetic relatives (i.e., kin) could prompt increased kin-directed altruism, thereby offsetting decreased reproduction by helping kin reproduce. These traits include childhood separation anxiety and adulthood neuroticism, which have been associated with feminine gender expression. In prior research, gay men with a receptive (Bottom or Versatile) anal sex role (ASR) reported greater childhood gender nonconformity (GNC) than those with an insertive (Top) ASR. We examined whether ASR groups also differed on recalled childhood separation anxiety and adulthood neuroticism. The Separation Anxiety Scale-Revised and Big-Five Personality Inventory - short form were completed by 350 gay and 146 heterosexual men. For neuroticism, ASR preference groups differed from heterosexual men but not from one another. Gay men who preferred a Bottom or Versatile ASR reported higher recalled childhood separation anxiety than Tops and heterosexual men. Recalled childhood GNC mediated ASR group differences with heterosexual men on childhood separation anxiety. These results indicate that subgroups of gay men delineated by ASR differ on an evolutionarily relevant developmental trait, childhood separation anxiety.
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Affiliation(s)
- Ashlyn Swift-Gallant
- Department of Psychology, University of Toronto Mississauga
- Department of Psychology, Memorial University of Newfoundland
| | | | - D Ashley Monks
- Department of Psychology, University of Toronto Mississauga
- Department of Cells and Systems Biology, University of Toronto
| | - Doug P VanderLaan
- Department of Psychology, University of Toronto Mississauga
- Child and Youth Psychiatry, Centre for Addiction and Mental Health
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13
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Cui J, Pei M, Su Y. Gender-related friend preferences of youths with different sexual orientations: the effects of gender role and sexual attraction. PSYCHOLOGY & SEXUALITY 2022. [DOI: 10.1080/19419899.2020.1734066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Jingmeng Cui
- Beijing Key Laboratory of Behavior and Mental Health, School of Psychological and Cognitive Sciences, Peking University, Beijing, China
| | - Meng Pei
- Beijing Key Laboratory of Behavior and Mental Health, School of Psychological and Cognitive Sciences, Peking University, Beijing, China
| | - Yanjie Su
- Beijing Key Laboratory of Behavior and Mental Health, School of Psychological and Cognitive Sciences, Peking University, Beijing, China
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14
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Gómez Jiménez FR, Vasey PL. Facial Attractiveness of the Sisters of Istmo Zapotec Men and Muxes: Implications for the Evolution of Male Androphilia. JOURNAL OF SEX RESEARCH 2022; 59:354-359. [PMID: 34213985 DOI: 10.1080/00224499.2021.1943737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Research shows that the female relatives of androphilic (i.e., sexually attracted to adult males) males have more children than the female relatives of gynephilic (i.e., sexually attracted to adult females) males. The mechanisms by which this occurs are unclear. The hypergyny hypothesis suggests that the female relatives of androphilic males have elevated attractiveness which allows them to obtain male partners with higher socioeconomic status, which in turn, provide them with more resources to produce and sustain multiple offspring. We tested whether the female kin of male androphiles are characterized by elevated attractiveness compared to the female kin of male gynephiles. The research was conducted among the Istmo Zapotec from Oaxaca, Mexico, where androphilic males are recognized as a third gender, muxes. We recruited 115 gynephilic men who rated the facial attractiveness of 27 women with at least one muxe sibling and 27 women with only gynephilic male siblings (i.e., control sisters). The results showed that gynephilic men found the faces of control sisters more attractive than the faces of muxe sisters. This finding is inconsistent with the hypergyny hypothesis and suggests that elevated facial attractiveness is not the mechanism by which the female relatives of androphilic males achieve elevated reproduction.
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Affiliation(s)
| | - Paul L Vasey
- Department of Psychology, University of Lethbridge
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15
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Gómez Jiménez FR, Vasey PL. Kin-directed altruism and the evolution of male androphilia among Istmo Zapotec Muxes. EVOL HUM BEHAV 2022. [DOI: 10.1016/j.evolhumbehav.2022.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Sanders AR, Beecham GW, Guo S, Badner JA, Bocklandt S, Mustanski BS, Hamer DH, Martin ER. Genome-Wide Linkage Study Meta-Analysis of Male Sexual Orientation. ARCHIVES OF SEXUAL BEHAVIOR 2021; 50:3371-3375. [PMID: 34080073 PMCID: PMC8604844 DOI: 10.1007/s10508-021-02035-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 05/01/2021] [Accepted: 05/04/2021] [Indexed: 05/26/2023]
Abstract
Male sexual orientation is a scientifically and socially important trait shown by family and twin studies to be influenced by environmental and complex genetic factors. Individual genome-wide linkage studies (GWLS) have been conducted, but not jointly analyzed. Two main datasets account for > 90% of the published GWLS concordant sibling pairs on the trait and are jointly analyzed here: MGSOSO (Molecular Genetic Study of Sexual Orientation; 409 concordant sibling pairs in 384 families, Sanders et al. (2015)) and Hamer (155 concordant sibling pairs in 145 families, Mustanski et al. (2005)). We conducted multipoint linkage analyses with Merlin on the datasets separately since they were genotyped differently, integrated genetic marker positions, and combined the resultant LOD (logarithm of the odds) scores at each 1 cM grid position. We continue to find the strongest linkage support at pericentromeric chromosome 8 and chromosome Xq28. We also incorporated the remaining published GWLS dataset (on 55 families) by using meta-analytic approaches on published summary statistics. The meta-analysis has maximized the positional information from GWLS of currently available family resources and can help prioritize findings from genome-wide association studies (GWAS) and other approaches. Although increasing evidence highlights genetic contributions to male sexual orientation, our current understanding of contributory loci is still limited, consistent with the complexity of the trait. Further increasing genetic knowledge about male sexual orientation, especially via large GWAS, should help advance our understanding of the biology of this important trait.
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Affiliation(s)
- Alan R Sanders
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem, 1001 University Place, Evanston, IL, 60201, USA.
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA.
| | - Gary W Beecham
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Shengru Guo
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | | | - Sven Bocklandt
- National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Brian S Mustanski
- Department of Medical Social Sciences, Northwestern University, Evanston, IL, USA
| | - Dean H Hamer
- National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Eden R Martin
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA
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17
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Sanders AR, Beecham GW, Guo S, Dawood K, Rieger G, Krishnappa RS, Kolundzija AB, Bailey JM, Martin ER. Genome-Wide Linkage and Association Study of Childhood Gender Nonconformity in Males. ARCHIVES OF SEXUAL BEHAVIOR 2021; 50:3377-3383. [PMID: 34518958 PMCID: PMC8604823 DOI: 10.1007/s10508-021-02146-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
Male sexual orientation is influenced by environmental and complex genetic factors. Childhood gender nonconformity (CGN) is one of the strongest correlates of homosexuality with substantial familiality. We studied brothers in families with two or more homosexual brothers (409 concordant sibling pairs in 384 families, as well as their heterosexual brothers), who self-recalled their CGN. To map loci for CGN, we conducted a genome-wide linkage scan (GWLS) using SNP genotypes. The strongest linkage peaks, each with significant or suggestive two-point LOD scores and multipoint LOD score support, were on chromosomes 5q31 (maximum two-point LOD = 4.45), 6q12 (maximum two-point LOD = 3.64), 7q33 (maximum two-point LOD = 3.09), and 8q24 (maximum two-point LOD = 3.67), with the latter not overlapping with previously reported strongest linkage region for male sexual orientation on pericentromeric chromosome 8. Family-based association analyses were used to identify associated variants in the linkage regions, with a cluster of SNPs (minimum association p = 1.3 × 10-8) found at the 5q31 linkage peak. Genome-wide, clusters of multiple SNPs in the 10-6 to 10-8 p-value range were found at chromosomes 5p13, 5q31, 7q32, 8p22, and 10q23, highlighting glutamate-related genes. This is the first reported GWLS and genome-wide association study on CGN. Further increasing genetic knowledge about CGN and its relationships to male sexual orientation should help advance our understanding of the biology of these associated traits.
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Affiliation(s)
- Alan R Sanders
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem Research Institute, 1001 University Place, Evanston, IL, 60201, USA.
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA.
| | - Gary W Beecham
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Shengru Guo
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Khytam Dawood
- Department of Psychology, Pennsylvania State University, University Park, PA, USA
| | - Gerulf Rieger
- Department of Psychology, University of Essex, Colchester, UK
| | - Ritesha S Krishnappa
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, Elmhurst, NY, USA
| | | | - J Michael Bailey
- Department of Psychology, Northwestern University, Evanston, IL, USA
| | - Eden R Martin
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, USA
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA
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18
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Hu SH, Li HM, Yu H, Liu Y, Liu CX, Zuo XB, Lu J, Jiang JJ, Xi CX, Huang BC, Xu HJ, Hu JB, Lai JB, Huang ML, Liu JN, Xu DG, Guo XC, Wu W, Wu X, Jiang L, Li M, Zhang GP, Huang JW, Wei N, Lv W, Duan JF, Qi HL, Hu CC, Chen JK, Zhou WH, Xu WJ, Liu CF, Liang HY, Du J, Zheng SF, Lu QL, Zheng L, Hu XW, Chen FX, Chen P, Zhu B, Xu LJ, Ni ZM, Fang YZ, Yang ZK, Shan XR, Zheng ED, Zhang F, Zhou QQ, Rao Y, Swaab D, Yue WH, Xu Y. Discovery of new genetic loci for male sexual orientation in Han population. Cell Discov 2021; 7:103. [PMID: 34719679 PMCID: PMC8558329 DOI: 10.1038/s41421-021-00341-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 08/31/2021] [Indexed: 12/12/2022] Open
Abstract
Epidemiological studies have demonstrated that the genetic factors partly influence the development of same-sex sexual behavior, but most genetic studies have focused on people of primarily European ancestry, potentially missing important biological insights. Here, we performed a two-stage genome-wide association study (GWAS) with a total sample of 1478 homosexual males and 3313 heterosexual males in Han Chinese populations and identified two genetic loci (rs17320865, Xq27.3, FMR1NB, Pmeta = 8.36 × 10-8, OR = 1.29; rs7259428, 19q12, ZNF536, Pmeta = 7.58 × 10-8, OR = 0.75) showing consistent association with male sexual orientation. A fixed-effect meta-analysis including individuals of Han Chinese (n = 4791) and European ancestries (n = 408,995) revealed 3 genome-wide significant loci of same-sex sexual behavior (rs9677294, 2p22.1, SLC8A1, Pmeta = 1.95 × 10-8; rs2414487, 15q21.3, LOC145783, Pmeta = 4.53 × 10-9; rs2106525, 7q31.1, MDFIC, Pmeta = 6.24 × 10-9). These findings may provide new insights into the genetic basis of male sexual orientation from a wider population scope. Furthermore, we defined the average ZNF536-immunoreactivity (ZNF536-ir) concentration in the suprachiasmatic nucleus (SCN) as lower in homosexual individuals than in heterosexual individuals (0.011 ± 0.001 vs 0.021 ± 0.004, P = 0.013) in a postmortem study. In addition, compared with heterosexuals, the percentage of ZNF536 stained area in the SCN was also smaller in the homosexuals (0.075 ± 0.040 vs 0.137 ± 0.103, P = 0.043). More homosexual preference was observed in FMR1NB-knockout mice and we also found significant differences in the expression of serotonin, dopamine, and inflammation pathways that were reported to be related to sexual orientation when comparing CRISPR-mediated FMR1NB knockout mice to matched wild-type target C57 male mice.
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Affiliation(s)
- Shao-Hua Hu
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
- National Human Brain Bank for Health and Disease, Hangzhou, Hangzhou, Zhejiang, China
- Brain Research Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Hai-Mei Li
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Hao Yu
- Department of Psychiatry, Jining Medical University, 133 Hehua Rd, Jining, Shandong, China
| | - Yan Liu
- Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Chen-Xing Liu
- Department of Human Genetics, University of Pittsburgh, Pittsburgh, PA, USA
| | - Xian-Bo Zuo
- Institute of Dermatology and Department of Dermatology at First Hospital, Anhui Medical University, Hefei, Anhui, China
| | - Jing Lu
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Jia-Jun Jiang
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Cai-Xi Xi
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Bo-Chao Huang
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Hu-Ji Xu
- Department of General Office, Center for Disease Control of Jianggan District, Hangzhou, Zhejiang, China
| | - Jian-Bo Hu
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Jian-Bo Lai
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Man-Li Huang
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Jian-Ning Liu
- Department of Clinical Laboratory, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Dan-Ge Xu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xi-Chao Guo
- Department of Clinical Laboratory, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Wei Wu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xin Wu
- Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, The Second Military Medial University, Shanghai, China
| | - Lei Jiang
- Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, The Second Military Medial University, Shanghai, China
| | - Meng Li
- Department of Rheumatology and Immunology, Shanghai Changzheng Hospital, The Second Military Medial University, Shanghai, China
| | - Guang-Ping Zhang
- Department of Clinical Laboratory, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jin-Wen Huang
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Ning Wei
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Wen Lv
- Department of Psychiatry, Seventh Hangzhou Hospital, Hangzhou, Zhejiang, China
| | - Jin-Feng Duan
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Hong-Li Qi
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Chan-Chan Hu
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jing-Kai Chen
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Wei-Hua Zhou
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Wei-Juan Xu
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China
| | - Chen-Feng Liu
- Medicines&Biochemical Products Branch, Zhejiang Medicine &Health Products I/E CO., Ltd, Hangzhou, Zhejiang, China
| | - Hai-Yong Liang
- BioMiao Biological Technology (Beijing) Co., Ltd, Beijing, China
| | - Jing Du
- Beijing Emei Tongde Technology Development Co., Ltd, Beijing, China
| | - Shu-Fa Zheng
- Department of Clinical Laboratory, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Qiao-Ling Lu
- Department of Aids Venereal Disease Control and Prevention, Shaoxing Center for Disease Control and Prevention, Shaoxing, Zhejiang, China
| | - Lin Zheng
- Department of Prevention and Treatment of AIDS and Sexually Transmitted Diseases, Center for Disease Control and Prevention of Xihu District, Hangzhou, Zhejiang, China
| | - Xiao-Wei Hu
- Department of Clinical Laboratory, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Feng-Xiang Chen
- Department of Clinical Laboratory, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Peng Chen
- International medical center, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Biao Zhu
- Department of Infectious Disease, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Li-Jun Xu
- Department of Infectious Disease, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Zhi-Min Ni
- Department of Disease Control, Center for Disease Control of Jianggan District, Hangzhou, Zhejiang, China
| | - Ye-Zhen Fang
- Department of Laboratory, Center for Disease Control of Jianggan District, Hangzhou, Zhejiang, China
| | - Zuo-Kai Yang
- Department of Aids Venereal Disease Control and Prevention, Shaoxing Center for Disease Control and Prevention, Shaoxing, Zhejiang, China
| | - Xin-Ren Shan
- Department of Aids Venereal Disease Control and Prevention, Shaoxing Center for Disease Control and Prevention, Shaoxing, Zhejiang, China
| | - En-de Zheng
- Beijing ViewSolid Biotechnology, Beijing, China
| | - Fan Zhang
- Shanghai OE Biotech. Co., Ltd, Beijing, China
| | | | - Yi Rao
- Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
- Peking-Tsinghua Center for Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking University School of Life Sciences, Beijing, China
| | - Dick Swaab
- Netherlands Institute for Neuroscience, Amsterdam, 1105 BA, The Netherlands
| | - Wei-Hua Yue
- Institute of Mental Health, National Clinical Research Center for Mental Disorders, Peking University Sixth Hospital, Beijing, China.
- NHC Key Laboratory of Mental Health, & Research Unit of Diagnosis and Treatment of Mood Cognitive Disorder (2018RU006), Chinese Academy of Medical Sciences, Beijing, China.
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, China.
| | - Yi Xu
- Department of Psychiatry, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
- The Key Laboratory of Mental Disorder Management in Zhejiang Province, Hangzhou, Zhejiang, China.
- National Human Brain Bank for Health and Disease, Hangzhou, Hangzhou, Zhejiang, China.
- Brain Research Institute, Zhejiang University, Hangzhou, Zhejiang, China.
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19
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Swaab DF, Wolff SEC, Bao AM. Sexual differentiation of the human hypothalamus: Relationship to gender identity and sexual orientation. HANDBOOK OF CLINICAL NEUROLOGY 2021; 181:427-443. [PMID: 34238476 DOI: 10.1016/b978-0-12-820683-6.00031-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Gender identity (an individual's perception of being male or female) and sexual orientation (heterosexuality, homosexuality, or bisexuality) are programmed into our brain during early development. During the intrauterine period in the second half of pregnancy, a testosterone surge masculinizes the fetal male brain. If such a testosterone surge does not occur, this will result in a feminine brain. As sexual differentiation of the brain takes place at a much later stage in development than sexual differentiation of the genitals, these two processes can be influenced independently of each other and can result in gender dysphoria. Nature produces a great variability for all aspects of sexual differentiation of the brain. Mechanisms involved in sexual differentiation of the brain include hormones, genetics, epigenetics, endocrine disruptors, immune response, and self-organization. Furthermore, structural and functional differences in the hypothalamus relating to gender dysphoria and sexual orientation are described in this review. All the genetic, postmortem, and in vivo scanning observations support the neurobiological theory about the origin of gender dysphoria, i.e., it is the sizes of brain structures, the neuron numbers, the molecular composition, functions, and connectivity of brain structures that determine our gender identity or sexual orientation. There is no evidence that one's postnatal social environment plays a crucial role in the development of gender identity or sexual orientation.
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Affiliation(s)
- Dick F Swaab
- Department Neuropsychiatric Disorders, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands
| | - Samantha E C Wolff
- Department Neuropsychiatric Disorders, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands
| | - Ai-Min Bao
- Department of Neurobiology and Department of Neurology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China; NHC and CAMS Key Laboratory of Medical Neurobiology, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China.
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20
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Okamoto N, Yoshino K, Kitagawa S, Fujii R, Hamada S, Ikenouchi A, Konishi Y, Ueda N, Eto Y, Tsutsumi Y, Yoshimura R. Association Between Serum Insulin-Like Growth Factor 1 Levels and the Clinical Symptoms of Chronic Schizophrenia: Preliminary Findings. Front Psychiatry 2021; 12:653802. [PMID: 33746806 PMCID: PMC7966725 DOI: 10.3389/fpsyt.2021.653802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 02/05/2021] [Indexed: 11/30/2022] Open
Abstract
Purpose: Insulin-like growth factor 1 (IGF-1) is a trophic mediator that is regulated by growth hormone and associated with the proliferation, development, and growth of neural cells. IGF-1 may be associated with the pathophysiology of schizophrenia, but this association remains controversial. This study aimed to investigate the relationship between serum IGF-1 levels and psychiatric symptoms in patients with chronic schizophrenia. Patients and Methods: A total of 65 patients were recruited from the University of Occupational and Environmental Health, Komine Eto Hospital, Moji Matsugae Hospital, Shin-Moji Hospital, and Tsutsumi Hospital in Kitakyushu between September 2019 and June 2020. Further, 20 healthy age- and sex-matched control participants were recruited from the Komine Eto Hospital and the University of Occupational and Environmental Health. Patients with schizophrenia were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Drug-Induced Extrapyramidal Symptoms Scale. Serum levels of free plus albumin-bound IGF-1 (IGF-1) were measured by immunoradiometric assay. The measurements were performed using antibody beads for bound/free separation. Associations between serum IGF-1 levels and the PANSS scores were determined. We also examined the associations between serum IGF-1 levels and diabetes, antipsychotic drug use, and disease duration. Results: No significant difference was found in the serum IGF-1 level between patients with schizophrenia and healthy controls. Serum IGF-1 levels were significantly negatively correlated with the PANSS total score (R 2 = 0.06, p = 0.015) and PANSS general score (R 2 = 0.088, p = 0.008), but not with the PANSS positive scores and PANSS negative scores. Serum IGF-1 levels were not related to the prevalence of diabetes (p = 0.64). However, a significant correlation was observed between serum IGF-1 levels and age (B = -1.88, p < 0.0001). Serum IGF-1 levels could not distinguish patients with schizophrenia and healthy controls. Conclusion: The association between serum IGF-1 levels and psychiatric symptoms may be complicated in patients with chronic schizophrenia.
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Affiliation(s)
- Naomichi Okamoto
- Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan
| | | | - Shogo Kitagawa
- Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Rintaro Fujii
- Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Shinsuke Hamada
- Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Atsuko Ikenouchi
- Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Yuki Konishi
- Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan
| | | | | | | | - Reiji Yoshimura
- Department of Psychiatry, University of Occupational and Environmental Health, Kitakyushu, Japan
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21
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Skorska MN, Coome LA, Zahran A, Peragine DE, VanderLaan DP. Facial Attractiveness of Sisters of Thai Gay Men and Sao Praphet Song. JOURNAL OF SEX RESEARCH 2021; 58:116-121. [PMID: 32239969 DOI: 10.1080/00224499.2020.1742858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Androphilia refers to sexual attraction toward adult males. Androphilic males' female genetic relatives might offset the fitness cost of androphilia by having elevated numbers of offspring. Increased attractiveness relative to other women may enable these females to marry up the social hierarchy, providing greater access to resources to support more offspring. In Thailand, there is a marked status hierarchy and male androphiles are highly visible - identifying as gay men or as a third gender known as sao praphet song. Thus, a field experiment was conducted in which 208 heterosexual men rated the facial attractiveness of 25 sisters of Thai gay men or sao praphet song and 25 comparison women with no known same-sex attracted relatives. Contrary to the prediction, the comparison group was rated as more attractive than the sisters, casting doubt on hypotheses that posit greater attractiveness of female relatives of male androphiles as a proximate mechanism facilitating the evolutionary maintenance of genes influencing male androphilia. Also, men from rural areas rated the women, regardless of group, as more attractive than men from urban areas, consistent with some prior studies showing rural-urban differences in perceptions of attractiveness.
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Affiliation(s)
| | | | - Adhm Zahran
- Department of Psychology, University of Toronto Mississauga
| | | | - Doug P VanderLaan
- Department of Psychology, University of Toronto Mississauga
- Child and Youth Psychiatry, Centre for Addiction and Mental Health
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22
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Bailey JM, Rieger G, Krishnappa RS, Kolundzija AB, Dawood K, Sanders AR. Familiality of Gender Nonconformity Among Homosexual Men. ARCHIVES OF SEXUAL BEHAVIOR 2020; 49:2461-2468. [PMID: 31950380 DOI: 10.1007/s10508-020-01626-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 01/01/2020] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
We examined whether recalled childhood gender nonconformity and self-reported adult gender nonconformity is familial, using data from 1154 families selected for having at least two homosexual brothers. Specifically, we examined the extent to which homosexual men's variation in gender nonconformity runs in families by examining pairs of genetic brothers who were both homosexual (N = 672-697 full sibling concordant pairs). We also examined similarity between homosexual and heterosexual brothers (N = 79-82 full sibling discordant pairs). Consistent with past studies, concordant pairs yielded modest positive correlations consistent with moderate genetic and/or familial environmental effects on gender nonconformity. Unlike results of smaller past studies, discordant pairs also yielded modest positive, though nonsignificant, correlations. Our results support the feasibility of supplementing genetic studies of male sexual orientation with analyses of gender nonconformity variation.
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Affiliation(s)
- J Michael Bailey
- Department of Psychology, Northwestern University, 2029 Sheridan Rd., Evanston, IL, 60208, USA.
| | - Gerulf Rieger
- Department of Psychology, University of Essex, Colchester, UK
| | - Ritesha S Krishnappa
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Khytam Dawood
- Department of Psychology, The Pennsylvania State University, University Park, PA, USA
| | - Alan R Sanders
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem Research Institute, Evanston, IL, USA
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
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23
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Allen MS, Robson DA. Personality and Sexual Orientation: New Data and Meta-analysis. JOURNAL OF SEX RESEARCH 2020; 57:953-965. [PMID: 32510233 DOI: 10.1080/00224499.2020.1768204] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This research explored associations between personality and sexual orientation. In Study 1, we explored whether the Big Five trait dimensions relate to sexual orientation in a nationally representative sample of Australian adults (n = 13,351). Personality differences were observed between those who identified as heterosexual (straight), bisexual, and homosexual (gay/lesbian) on all five measured traits. In Study 2, we conducted an updated systematic review and meta-analysis of personality and sexual orientation. A total of 21 studies (35 independent samples, 262 effect sizes) comprising 377,951 men and women were identified that satisfied inclusion criteria. Results showed that bisexual individuals reported higher levels of openness than homosexual individuals, who in turn, reported higher levels of openness than heterosexual individuals. Bisexual individuals also report lower levels of conscientiousness than both heterosexual and homosexual individuals. Sex moderation effects showed that homosexual men scored higher than heterosexual men on neuroticism, agreeableness and conscientiousness, whereas homosexual women scored lower than heterosexual women on extraversion, agreeableness, and conscientiousness. There was also evidence that personality differences between sexual orientation categories tend to decline with age. These findings align with the gender-shift hypothesis and should be of interest to theorists working in personality science and sexual identity development.
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24
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Balthazart J. Sexual partner preference in animals and humans. Neurosci Biobehav Rev 2020; 115:34-47. [PMID: 32450091 PMCID: PMC7484171 DOI: 10.1016/j.neubiorev.2020.03.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 03/11/2020] [Accepted: 03/24/2020] [Indexed: 12/25/2022]
Abstract
Sex differences in brain and behavior of animals including humans result from an interaction between biological and environmental influences. This is also true for the differences between men and women concerning sexual orientation. Sexual differentiation is mediated by three groups of biological mechanisms: early actions of sex steroids, more direct actions of sex-specific genes not mediated by gonadal sex steroids and epigenetic mechanisms. Differential interactions with parents and conspecifics have additionally long-term influences on behavior. This presentation reviews available evidence indicating that these different mechanisms play a significant role in the control of sexual partner preference in animals and humans, in other words the homosexual versus heterosexual orientation. Clinical and epidemiological studies of phenotypically selected populations indicate that early actions of hormones and genetic factors clearly contribute to the determination of sexual orientation. The maternal embryonic environment also modifies the incidence of male homosexuality via immunological mechanisms. The relative contribution of each of these mechanisms remains however to be determined.
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25
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Bogaert AF, Skorska MN. A short review of biological research on the development of sexual orientation. Horm Behav 2020; 119:104659. [PMID: 31911036 DOI: 10.1016/j.yhbeh.2019.104659] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 11/15/2022]
Abstract
We review research supporting biological mechanisms in the development of sexual orientation. This research includes studies on neural correlates, prenatal hormones and related physical/behavioral correlates, genetics, and the fraternal birth order effect (FBOE). These studies, taken together, have provided substantial support for biological influences underlying the development of sexual orientation, but questions remain unanswered, including how biological mechanisms may differ in contributing to men's and women's sexual orientation development.
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Affiliation(s)
- Anthony F Bogaert
- Department of Health Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON L2S 3A1, Canada; Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON L2S 3A1, Canada.
| | - Malvina N Skorska
- Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON L2S 3A1, Canada; Department of Psychology, University of Toronto Mississauga, 3359 Mississauga Road North, Mississauga, ON L5L 1C6, Canada.
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Gómez Jiménez FR, Semenyna SW, Vasey PL. Offspring Production Among the Relatives of Istmo Zapotec Men and Muxes. ARCHIVES OF SEXUAL BEHAVIOR 2020; 49:581-594. [PMID: 31897830 DOI: 10.1007/s10508-019-01611-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/12/2019] [Accepted: 12/14/2019] [Indexed: 06/10/2023]
Abstract
Male androphilia (i.e., sexual attraction toward adult males) is influenced by biological factors, reliably occurs across diverse cultures, and has persisted over evolutionary time despite the fact that it reduces reproduction. One possible solution to this evolutionary paradox is the sexually antagonistic gene hypothesis (SAGH), which states that genes associated with male androphilia reduce reproduction when present in males but increase reproduction when present in their female relatives. The present study tested the SAGH among the Istmo Zapotec-a non-Euro-American culture in Oaxaca, Mexico, where transgender and cisgender androphilic males are known as muxe gunaa and muxe nguiiu, respectively. To test the SAGH, we compared offspring production by the biological relatives of muxe gunaa (n = 115), muxe nguiiu (n = 112), and gynephilic men (i.e., cisgender males who are sexually attracted to adult females; n = 171). The mothers and paternal aunts of muxe gunaa had higher offspring production than those of muxe nguiiu. Additionally, the relatives of muxe gunaa had more offspring than those of gynephilic men, whereas no such differences were found between the families of gynephilic men and muxe nguiiu. Elevated reproduction by the mothers and, particularly the aunts, of muxe gunaa is consistent with the SAGH. However, the absence of group differences between gynephilic men and muxe nguiiu, and the group differences between the two types of muxes are not predicted by the SAGH. This is the first study to demonstrate reproductive differences between kin of transgender and cisgender androphilic males within the same non-Euro-American culture.
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Affiliation(s)
- Francisco R Gómez Jiménez
- Department of Psychology, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada.
| | - Scott W Semenyna
- Department of Psychology, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada
| | - Paul L Vasey
- Department of Psychology, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada
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Abstract
OBJECTIVE Non-heterosexual populations experience poorer mental health outcomes than their heterosexual counterparts. Few studies, however, have examined how mental health varies across the continuum of sexual orientation. Nor has any study examined possible links between sexual orientation and traits of impulsivity and compulsivity, which contribute to functional impairment across a broad spectrum of psychiatric disorders. To address these limitations, the present study sought to identify addictive and impulsive/compulsive problems associated with sexuality in a university sample. METHODS A 156-item anonymous survey was distributed via email to 9449 students at a public university in the United States. Sexual orientation was assessed using the Klein Sexual Orientation Grid, a modification of the Kinsey scale. Current use of alcohol and drugs, mental health status, and academic performance were also assessed, along with valid trait measures of impulsivity and compulsivity. RESULTS Same-sex attractions were significantly correlated with a range of mental health problems and substance use. Additionally, same-sex attraction was significantly correlated with certain behavioral addictions (compulsive sexual behavior and binge eating disorder) as well as impulsive/compulsive traits. There was no relationship between academic performance and sexual attraction. CONCLUSION Same-sex sexuality is associated with impulsive/compulsive behavior and addiction. These health disparities may be related to stable individual differences in self-control.
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Wang Y, Wu H, Sun ZS. The biological basis of sexual orientation: How hormonal, genetic, and environmental factors influence to whom we are sexually attracted. Front Neuroendocrinol 2019; 55:100798. [PMID: 31593707 DOI: 10.1016/j.yfrne.2019.100798] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 09/29/2019] [Accepted: 10/03/2019] [Indexed: 12/11/2022]
Abstract
Humans develop relatively stable attractions to sexual partners during maturation and present a spectrum of sexual orientation from homosexuality to heterosexuality encompassing varying degrees of bisexuality, with some individuals also displaying asexuality. Sexual orientation represents a basic life phenomenon for humans. However, the molecular mechanisms underlying these diverse traits of sexual orientation remain highly controversial. In this review, we systematically discuss recent advancements in sexual orientation research, including those related to measurements and associated brain regions. Current findings regarding sexual orientation modulation by hormonal, genetic, maternal immune system, and environmental factors are summarized in both human and model systems. We also emphasize that future studies should recognize the differences between males and females and pay more attention to minor traits and the epigenetic regulation of sexual orientation. A comprehensive view of sexual orientation may promote our understanding of the biological basis of sex, and that of human reproduction, and evolution.
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Affiliation(s)
- Yan Wang
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
| | - Haoda Wu
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China; Sino-Danish College, University of the Chinese Academy of Sciences, Beijing 100190, China
| | - Zhong Sheng Sun
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China; Sino-Danish College, University of the Chinese Academy of Sciences, Beijing 100190, China; Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou 325000, China.
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Agana MG, Greydanus DE, Indyk JA, Calles JL, Kushner J, Leibowitz S, Chelvakumar G, Cabral MD. Caring for the transgender adolescent and young adult: Current concepts of an evolving process in the 21st century. Dis Mon 2019; 65:303-356. [DOI: 10.1016/j.disamonth.2019.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Ganna A, Verweij KJH, Nivard MG, Maier R, Wedow R, Busch AS, Abdellaoui A, Guo S, Sathirapongsasuti JF, Lichtenstein P, Lundström S, Långström N, Auton A, Harris KM, Beecham GW, Martin ER, Sanders AR, Perry JRB, Neale BM, Zietsch BP. Large-scale GWAS reveals insights into the genetic architecture of same-sex sexual behavior. Science 2019; 365:eaat7693. [PMID: 31467194 PMCID: PMC7082777 DOI: 10.1126/science.aat7693] [Citation(s) in RCA: 151] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 07/22/2019] [Indexed: 12/11/2022]
Abstract
Twin and family studies have shown that same-sex sexual behavior is partly genetically influenced, but previous searches for specific genes involved have been underpowered. We performed a genome-wide association study (GWAS) on 477,522 individuals, revealing five loci significantly associated with same-sex sexual behavior. In aggregate, all tested genetic variants accounted for 8 to 25% of variation in same-sex sexual behavior, only partially overlapped between males and females, and do not allow meaningful prediction of an individual's sexual behavior. Comparing these GWAS results with those for the proportion of same-sex to total number of sexual partners among nonheterosexuals suggests that there is no single continuum from opposite-sex to same-sex sexual behavior. Overall, our findings provide insights into the genetics underlying same-sex sexual behavior and underscore the complexity of sexuality.
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Affiliation(s)
- Andrea Ganna
- Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Karin J H Verweij
- Department of Psychiatry, Amsterdam University Medical Centers (UMC), location AMC, University of Amsterdam, Meibergdreef 5, 1105 AZ Amsterdam, Netherlands
| | - Michel G Nivard
- Department of Biological Psychology, Vrije Universiteit Amsterdam, 1081 BT, Amsterdam, Netherlands
| | - Robert Maier
- Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Robbee Wedow
- Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Department of Sociology, Harvard University, Cambridge, MA 02138, USA
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA 02115, USA
- Department of Sociology, University of Colorado, Boulder, CO 80309-0483, USA
- Health and Society Program and Population Program, Institute of Behavioral Science, University of Colorado, Boulder, CO 80309-0483, USA
- Institute for Behavioral Genetics, University of Colorado, Boulder, CO 80309-0483, USA
| | - Alexander S Busch
- Medical Research Council (MRC) Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, UK
- Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- International Center for Research and Research Training in Endocrine Disruption of Male Reproduction and Child Health (EDMaRC), Rigshospitalet, Copenhagen, Denmark
| | - Abdel Abdellaoui
- Department of Psychiatry, Amsterdam University Medical Centers (UMC), location AMC, University of Amsterdam, Meibergdreef 5, 1105 AZ Amsterdam, Netherlands
| | - Shengru Guo
- Department of Human Genetics, University of Miami, Miami, FL 33136, USA
| | | | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Sebastian Lundström
- Centre for Ethics, Law and Mental Health, Gillberg Neuropsychiatry Centre, University of Gothenburg, Sweden
| | - Niklas Långström
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | | | - Kathleen Mullan Harris
- Carolina Population Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516, USA
- Department of Sociology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Gary W Beecham
- Department of Human Genetics, University of Miami, Miami, FL 33136, USA
| | - Eden R Martin
- Department of Human Genetics, University of Miami, Miami, FL 33136, USA
| | - Alan R Sanders
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem Research Institute, Evanston, IL 60201, USA
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL 60637, USA
| | - John R B Perry
- Medical Research Council (MRC) Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, UK
| | - Benjamin M Neale
- Analytic and Translational Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Brendan P Zietsch
- Centre for Psychology and Evolution, School of Psychology, University of Queensland, St. Lucia, Brisbane QLD 4072, Australia.
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Tran US, Kossmeier M, Voracek M. Associations of Bisexuality and Homosexuality with Handedness and Footedness: A Latent Variable Analysis Approach. ARCHIVES OF SEXUAL BEHAVIOR 2019; 48:1451-1461. [PMID: 30498915 PMCID: PMC6594983 DOI: 10.1007/s10508-018-1346-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 02/10/2018] [Accepted: 11/07/2018] [Indexed: 06/09/2023]
Abstract
Non-right-handedness appears to be more common among bisexuals and homosexuals than among heterosexuals, which might be indirect evidence of effects of prenatal androgen exposure. Current data suggest higher prenatal testosterone levels among bisexual and homosexual women, but are inconclusive for men. This study examined the association between sexual orientation and non-right-handedness for sex differences and whether higher rates of mixed-handedness, rather than left-handedness, might be the driving factor. This allowed for more specific tests regarding the predictions of two competing theories of prenatal androgen exposure, the Geschwind-Galaburda theory and the callosal hypothesis, than in previous research. Being a potentially better indicator of cerebral lateralization than handedness, associations with footedness were also explored. To counter inconsistencies and shortcomings of previous research, we utilized two large discovery and replication datasets (ns = 2368 and 1565) and applied latent variable analysis to reliably classify lateral preferences (i.e., handedness, footedness). This maximized the statistical conclusion validity and allowed for direct tests of replicability. Sexual orientation was differentially associated with lateral preferences among men and women. Associations among women were consistent with predictions of the Geschwind-Galaburda theory, whereas among men they were consistent with predictions of the callosal hypothesis. The results were further consistent with models of homosexuality that suggest a role of parental epigenetic marks on sexually dimorphic fetal development. Research efforts should be increased with regard to footedness and epigenetic theories of homosexuality.
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Affiliation(s)
- Ulrich S Tran
- Department of Basic Psychological Research and Research Methods, School of Psychology, University of Vienna, 1010, Vienna, Austria.
| | - Michael Kossmeier
- Department of Basic Psychological Research and Research Methods, School of Psychology, University of Vienna, 1010, Vienna, Austria
| | - Martin Voracek
- Department of Basic Psychological Research and Research Methods, School of Psychology, University of Vienna, 1010, Vienna, Austria
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32
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Swift-Gallant A, Coome LA, Aitken M, Monks DA, VanderLaan DP. Evidence for distinct biodevelopmental influences on male sexual orientation. Proc Natl Acad Sci U S A 2019; 116:12787-12792. [PMID: 31182568 PMCID: PMC6600923 DOI: 10.1073/pnas.1809920116] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Several biological mechanisms have been proposed to influence male sexual orientation, but the extent to which these mechanisms cooccur is unclear. Putative markers of biological processes are often used to evaluate the biological basis of male sexual orientation, including fraternal birth order, handedness, and familiality of same-sex sexual orientation; these biomarkers are proxies for immunological, endocrine, and genetic mechanisms. Here, we used latent profile analysis (LPA) to assess whether these biomarkers cluster within the same individuals or are present in different subgroups of nonheterosexual men. LPA defined four profiles of men based on these biomarkers: 1) A subgroup who did not have these biomarkers, 2) fraternal birth order, 3) handedness, and 4) familiality. While the majority of both heterosexual and nonheterosexual men were grouped in the profile that did not have any biomarker, the three profiles associated with a biomarker were composed primarily of nonheterosexual men. We then evaluated whether these subgroups differed on measures of gender nonconformity and personality that reliably show male sexual orientation differences. The subgroup without biomarkers was the most gender-conforming whereas the fraternal birth order subgroup was the most female-typical and agreeable, compared with the other profiles. Together, these findings suggest there are multiple distinct biodevelopmental pathways influencing same-sex sexual orientation in men.
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Affiliation(s)
- Ashlyn Swift-Gallant
- Department of Psychology, Memorial University of Newfoundland, St. John's, NL A1B 3X9, Canada;
| | - Lindsay A Coome
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
| | - Madison Aitken
- Department of Psychiatry, University of Toronto, Toronto, ON M5T 1R8, Canada
- Child, Youth, and Emerging Adult Program, Centre for Addiction and Mental Health, Toronto, ON M6J 1H4, Canada
| | - D Ashley Monks
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
| | - Doug P VanderLaan
- Department of Psychology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada;
- Child and Youth Psychiatry, Centre for Addiction and Mental Health, Toronto, ON M6J 1H4, Canada
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33
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Stroebel SS, O’Keefe SL, Griffee K, Harper-Dorton KV, Beard KW, Young DH, Swindell S, Stroupe WE, Steele K, Lawhon M, Kuo SY. Effects of the sex of the perpetrator on victims’ subsequent sexual behaviors and adulthood sexual orientations. COGENT PSYCHOLOGY 2019. [DOI: 10.1080/23311908.2018.1564424] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Sandra S. Stroebel
- School Psychology Program, Marshall University Graduate College, 100 Angus E. Peyton Drive, South Charleston, WV 25303-1600, USA
- Department of Psychology, Marshall University, One John Marshall Dr., Huntington, WV 25755, USA
| | - Stephen L. O’Keefe
- Department of Psychology, Marshall University, One John Marshall Dr., Huntington, WV 25755, USA
| | - Karen Griffee
- Division of Social Sciences, Concord University, PO Box 1000, Athens, WV 24712, USA
| | | | - Keith W. Beard
- Department of Psychology, Marshall University, One John Marshall Dr., Huntington, WV 25755, USA
| | - Debra H. Young
- Department of Social Work, Marshall University, One John Marshall Dr., Huntington, WV 25755, USA
| | - Sam Swindell
- Justice, Law and Public Safety Studies Department, Lewis University, Romeoville, IL and Samuel V.S. Swindell, Attorney and Counselor at Law, Christiansburg, VA, USA
| | - Walter E. Stroupe
- Department of Criminal Justice, West Virginia State University, P.O. Box 1000, Institute, WV 25112-1000, USA
| | - Kerri Steele
- Department of Criminal Justice, West Virginia State University, P.O. Box 1000, Institute, WV 25112-1000, USA
| | - Megan Lawhon
- Department of Psychology, Marshall University, One John Marshall Dr., Huntington, WV 25755, USA
| | - Shih-Ya Kuo
- Department of Criminal Justice, West Virginia State University, P.O. Box 1000, Institute, WV 25112-1000, USA
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Basavanhally T, Fonseca R, Uversky VN. Born This Way: Using Intrinsic Disorder to Map the Connections between SLITRKs, TSHR, and Male Sexual Orientation. Proteomics 2018; 18:e1800307. [PMID: 30156382 DOI: 10.1002/pmic.201800307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/03/2018] [Indexed: 12/15/2022]
Abstract
Recently, genome-wide association study reveals a significant association between specific single nucleotide polymorphisms (SNPs) in men and their sexual orientation. These SNPs (rs9547443 and rs1035144) reside in the intergenic region between the SLITRK5 and SLITRK6 genes and in the intronic region of the TSHR gene and might affect functionality of SLITRK5, SLITRK6, and TSHR proteins that are engaged in tight control of key developmental processes, such as neurite outgrowth and modulation, cellular differentiation, and hormonal regulation. SLITRK5 and SLITRK6 are single-pass transmembrane proteins, whereas TSHR is a heptahelical G protein-coupled receptor (GPCR). Mutations in these proteins are associated with various diseases and are linked to phenotypes found at a higher rate in homosexual men. A bioinformatics analysis of SLITRK5, SLITRK6, and TSHR proteins is conducted to look at their structure, protein interaction networks, and propensity for intrinsic disorder. It is assumed that this information might improve understanding of the roles that SLITRK5, SLITRK6, and TSHR play within neuronal and thyroidal tissues and give insight into the phenotypes associated with male homosexuality.
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Affiliation(s)
- Tara Basavanhally
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Renée Fonseca
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.,USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.,Protein Research Group, Institute for Biological Instrumentation of the Russian Academy of Sciences, 142290, Pushchino, Moscow, Russia
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35
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O'Hanlan KA, Gordon JC, Sullivan MW. Biological origins of sexual orientation and gender identity: Impact on health. Gynecol Oncol 2018; 149:33-42. [PMID: 29605047 DOI: 10.1016/j.ygyno.2017.11.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 10/30/2017] [Accepted: 11/07/2017] [Indexed: 01/19/2023]
Abstract
Gynecologic Oncologists are sometimes consulted to care for patients who present with diverse gender identities or sexual orientations. Clinicians can create more helpful relationships with their patients if they understand the etiologies of these diverse expressions of sexual humanity. Multidisciplinary evidence reveals that a sexually dimorphic spectrum of somatic and neurologic anatomy, traits and abilities, including sexual orientation and gender identity, are conferred together during the first half of pregnancy due to genetics, epigenetics and the diversity of timing and function of sex chromosomes, sex-determining protein secretion, gonadal hormone secretion, receptor levels, adrenal function, maternally ingested dietary hormones, fetal health, and many other factors. Multiple layers of evidence confirm that sexual orientation and gender identity are as biological, innate and immutable as the other traits conferred during that critical time in gestation. Negative social responses to diverse orientations or gender identities have caused marginalization of these individuals with resultant alienation from medical care, reduced self-care and reduced access to medical care. The increased risks for many diseases, including gynecologic cancers are reviewed. Gynecologic Oncologists can potentially create more effective healthcare relationships with their patients if they have this information.
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Affiliation(s)
- Katherine A O'Hanlan
- Laparoscopic Institute for Gynecology and Oncology (LIGO), 4370 Alpine Rd. Suite 104, Portola Valley, CA 94028, United States.
| | - Jennifer C Gordon
- University of Tennessee Health Sciences Center, Memphis, TN, United States.
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Abé C, Rahman Q, Långström N, Rydén E, Ingvar M, Landén M. Cortical brain structure and sexual orientation in adult females with bipolar disorder or attention deficit hyperactivity disorder. Brain Behav 2018; 8:e00998. [PMID: 29845776 PMCID: PMC6043709 DOI: 10.1002/brb3.998] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/29/2018] [Accepted: 04/19/2018] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Nonheterosexual individuals have higher risk of psychiatric morbidity. Together with growing evidence for sexual orientation-related brain differences, this raises the concern that sexual orientation may be an important factor to control for in neuroimaging studies of neuropsychiatric disorders. METHODS We studied sexual orientation in adult psychiatric patients with bipolar disorder (BD) or ADHD in a large clinical cohort (N = 154). We compared cortical brain structure in exclusively heterosexual women (HEW, n = 29) with that of nonexclusively heterosexual women (nHEW, n = 37) using surface-based reconstruction techniques provided by FreeSurfer. RESULTS The prevalence of nonheterosexual sexual orientation was tentatively higher than reported in general population samples. Consistent with previously reported cross-sex shifted brain patterns among homosexual individuals, nHEW patients showed significantly larger cortical volumes than HEW in medial occipital brain regions. CONCLUSION We found evidence for a sex-reversed difference in cortical volume among nonheterosexual female patients, which provides insights into the neurobiology of sexual orientation, and may provide the first clues toward a better neurobiological understanding of the association between sexual orientation and mental health. We also suggest that sexual orientation is an important factor to consider in future neuroimaging studies of populations with certain mental health disorders.
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Affiliation(s)
- Christoph Abé
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Qazi Rahman
- Department of Psychology, Institute of Psychiatry, King's College London, London, UK
| | - Niklas Långström
- Department of Neuroscience, Uppsala University, Uppsala, Sweden.,Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Eleonore Rydén
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Martin Ingvar
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Mikael Landén
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.,Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden
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37
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Roselli CE. Neurobiology of gender identity and sexual orientation. J Neuroendocrinol 2018; 30:e12562. [PMID: 29211317 PMCID: PMC6677266 DOI: 10.1111/jne.12562] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/03/2017] [Accepted: 11/28/2017] [Indexed: 12/15/2022]
Abstract
Sexual identity and sexual orientation are independent components of a person's sexual identity. These dimensions are most often in harmony with each other and with an individual's genital sex, although not always. The present review discusses the relationship of sexual identity and sexual orientation to prenatal factors that act to shape the development of the brain and the expression of sexual behaviours in animals and humans. One major influence discussed relates to organisational effects that the early hormone environment exerts on both gender identity and sexual orientation. Evidence that gender identity and sexual orientation are masculinised by prenatal exposure to testosterone and feminised in it absence is drawn from basic research in animals, correlations of biometric indices of androgen exposure and studies of clinical conditions associated with disorders in sexual development. There are, however, important exceptions to this theory that have yet to be resolved. Family and twin studies indicate that genes play a role, although no specific candidate genes have been identified. Evidence that relates to the number of older brothers implicates maternal immune responses as a contributing factor for male sexual orientation. It remains speculative how these influences might relate to each other and interact with postnatal socialisation. Nonetheless, despite the many challenges to research in this area, existing empirical evidence makes it clear that there is a significant biological contribution to the development of an individual's sexual identity and sexual orientation.
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Affiliation(s)
- C E Roselli
- Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA
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38
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Fisher AD, Ristori J, Morelli G, Maggi M. The molecular mechanisms of sexual orientation and gender identity. Mol Cell Endocrinol 2018; 467:3-13. [PMID: 28847741 DOI: 10.1016/j.mce.2017.08.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 08/02/2017] [Accepted: 08/15/2017] [Indexed: 12/21/2022]
Abstract
Differences between males and females are widely represented in nature. There are gender differences in phenotypes, personality traits, behaviors and interests, cognitive performance, and proneness to specific diseases. The most marked difference in humans is represented by sexual orientation and core gender identity, the origins of which are still controversial and far from being understood. Debates continue on whether sexual behavior and gender identity are a result of biological (nature) or cultural (nurture) factors, with biology possibly playing a major role. The main goal of this review is to summarize the studies available to date on the biological factors involved in the development of both sexual orientation and gender identity. A systematic search of published evidence was performed using Medline (from January 1948 to June 2017). Review of the relevant literature was based on authors' expertise. Indeed, different studies have documented the possible role and interaction of neuroanatomic, hormonal and genetic factors. The sexual dimorphic brain is considered the anatomical substrate of psychosexual development, on which genes and gonadal hormones may have a shaping effect. In particular, growing evidence shows that prenatal and pubertal sex hormones permanently affect human behavior. In addition, heritability studies have demonstrated a role of genetic components. However, a convincing candidate gene has not been identified. Future studies (e.i. genome wide studies) are needed to better clarify the complex interaction between genes, anatomy and hormonal influences on psychosexual development.
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Affiliation(s)
- Alessandra D Fisher
- Department of Experimental, Clinical and Biomedical Sciences, Careggi University Hospital, Florence, Italy
| | - Jiska Ristori
- Department of Experimental, Clinical and Biomedical Sciences, Careggi University Hospital, Florence, Italy
| | - Girolamo Morelli
- Department of Surgical, Medical, Molecular and of the Critical Area Pathology, University of Pisa, Pisa, Italy
| | - Mario Maggi
- Department of Experimental, Clinical and Biomedical Sciences, Careggi University Hospital, Florence, Italy.
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Experimental evolution with an insect model reveals that male homosexual behaviour occurs due to inaccurate mate choice. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.03.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Gómez FR, Semenyna SW, Court L, Vasey PL. Familial patterning and prevalence of male androphilia among Istmo Zapotec men and muxes. PLoS One 2018; 13:e0192683. [PMID: 29466410 PMCID: PMC5821324 DOI: 10.1371/journal.pone.0192683] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 11/08/2017] [Indexed: 11/18/2022] Open
Abstract
Male androphilia (i.e., male sexual attraction to other adult males) is known to cluster within families. Some studies demonstrate that male androphilia clusters in both the paternal and maternal familial lines, whereas other studies demonstrated that it clusters only in the latter. Most of these studies were conducted in Euro-American populations where fertility is low and the sexual orientation of male relatives can sometimes be difficult to ascertain. These two factors can potentially confound the results of such studies. To address these limitations, we examined the familial patterning of male androphilia among the Istmo Zapotec of Oaxaca, Mexico--a high fertility, non-Euro-American population where androphilic males are known locally as muxes, a third gender category. The Istmo Zapotec recognize two types of muxes--muxe gunaa and muxe nguiiu--who typify the transgender and cisgender forms of male androphilia, respectively. We compared the familial patterning of male androphilia between muxe gunaa and muxe nguiiu, as well as between gynephilic men and muxes (both cisgender and transgender forms combined). Istmo Zapotec muxe gunaa and muxe nguiiu exhibit similar familial patterning of male androphilia. Overall, muxes were characterized by significantly more muxe relatives than gynephilic men. This familial patterning was equivalent in both the paternal and maternal lines of muxes. The population prevalence rate of male androphilia was estimated to fall between 3.37-6.02% in the Istmo Zapotec. This is the first study that has compared cisgender and transgender androphilic males from the same high fertility population and demonstrated that the two do not differ with respect to the familial patterning of male androphilia.
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Affiliation(s)
- Francisco R. Gómez
- Department of Psychology, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Scott W. Semenyna
- Department of Psychology, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Lucas Court
- Department of Psychology, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Paul L. Vasey
- Department of Psychology, University of Lethbridge, Lethbridge, Alberta, Canada
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Gavrilets S, Friberg U, Rice WR. Understanding Homosexuality: Moving on from Patterns to Mechanisms. ARCHIVES OF SEXUAL BEHAVIOR 2018; 47:27-31. [PMID: 28986707 DOI: 10.1007/s10508-017-1092-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 09/26/2017] [Indexed: 06/07/2023]
Affiliation(s)
- Sergey Gavrilets
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, 37996, USA.
- Department of Mathematics, University of Tennessee, Knoxville, TN, USA.
- National Institute for Mathematical and Biological Synthesis, University of Tennessee, Knoxville, TN, USA.
| | - Urban Friberg
- IFM Biology, Linkoping University, Linkoping, Sweden
| | - William R Rice
- Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA, USA
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Qin JB, Zhao GL, Wang F, Cai YM, Lan LN, Yang L, Feng TJ. Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study. J Sex Med 2018; 15:29-42. [PMID: 29289372 DOI: 10.1016/j.jsxm.2017.11.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 10/16/2017] [Accepted: 11/20/2017] [Indexed: 11/20/2022]
Abstract
BACKGROUND Although it is widely acknowledged that genetic and environmental factors are involved in the development of male homosexuality, the causes are not fully understood. AIM To explore the association and interaction of childhood abuse experiences and genetic variants of the catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) genes with the development of male homosexuality. METHODS A case-control study of 537 exclusively homosexual men and 583 exclusively heterosexual men was conducted, with data collected from March 2013 to August 2015. Data were analyzed using χ2 tests and logistic regression models. OUTCOMES Sociodemographic characteristics, childhood abuse experiences, and polymorphisms of COMT at rs4680, rs4818, and rs6267 and MTHFR at rs1801133. RESULTS More frequent occurrence of physical (adjusted odds ratio [aOR] = 1.78), emotional (aOR = 2.07), and sexual (aOR = 2.53) abuse during childhood was significantly associated with the development of male homosexuality. The polymorphisms of MTHFR at rs1801133 and COMT at rs4818 also were significantly associated with the development of male homosexuality in the homozygote comparisons (T/T vs C/C at rs1801133, aOR = 1.68; G/G vs C/C at rs4818, aOR = 1.75). In addition, significant interaction effects between childhood abuse experiences and the COMT and MTHFR genetic variants on the development of male homosexuality were found. CLINICAL TRANSLATION This is the first time that an association of childhood abuse, COMT and MTHFR genetic variants, and their interactions with development of male homosexuality was exhaustively explored, which could help provide new insight into the etiology of male homosexuality. STRENGTHS AND LIMITATIONS Because homosexual men are a relatively obscure population, it was impossible to select the study participants by random sampling, which could lead to selection bias. In addition, because this was a case-control study, recall bias was inevitable, and we could not verify causality. CONCLUSIONS Childhood abuse and the COMT and MTHFR genetic variants could be positively associated with the development of homosexuality. However, it remains unknown how these factors jointly play a role in the development of homosexuality, and more studies in different ethnic populations and with a larger sample and a prospective design are required to confirm our findings. Qin J-B, Zhao G-L, Wang F, et al. Childhood Abuse Experiences and the COMT and MTHFR Genetic Variants Associated With Male Sexual Orientation in the Han Chinese Populations: A Case-Control Study. J Sex Med 2018;15:29-42.
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Affiliation(s)
- Jia-Bi Qin
- Department of Epidemiology and Health Statistics, School of Public Health, Central South University, Changsha, Hunan, China
| | - Guang-Lu Zhao
- Shenzhen Center for Chronic Disease Control, Shenzhen, China
| | - Feng Wang
- Shenzhen Center for Chronic Disease Control, Shenzhen, China
| | - Yu-Mao Cai
- Shenzhen Center for Chronic Disease Control, Shenzhen, China
| | - Li-Na Lan
- Shenzhen Center for Chronic Disease Control, Shenzhen, China
| | - Lin Yang
- Department of Epidemiology and Health Statistics, School of Public Health, Central South University, Changsha, Hunan, China
| | - Tie-Jian Feng
- Shenzhen Center for Chronic Disease Control, Shenzhen, China.
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Gaziano C. Adult attachment style and beliefs about public affairs and scientific issues. COGENT PSYCHOLOGY 2017. [DOI: 10.1080/23311908.2017.1279423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Cecilie Gaziano
- Research Solutions, Inc., 4511 Fremont Avenue South, Minneapolis, MN 55419-4744, USA
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Fraternal birth order effect on sexual orientation explained. Proc Natl Acad Sci U S A 2017; 115:234-236. [PMID: 29259109 DOI: 10.1073/pnas.1719534115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Sanders AR, Beecham GW, Guo S, Dawood K, Rieger G, Badner JA, Gershon ES, Krishnappa RS, Kolundzija AB, Duan J, Gejman PV, Bailey JM, Martin ER. Genome-Wide Association Study of Male Sexual Orientation. Sci Rep 2017; 7:16950. [PMID: 29217827 PMCID: PMC5721098 DOI: 10.1038/s41598-017-15736-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 10/31/2017] [Indexed: 11/11/2022] Open
Abstract
Family and twin studies suggest that genes play a role in male sexual orientation. We conducted a genome-wide association study (GWAS) of male sexual orientation on a primarily European ancestry sample of 1,077 homosexual men and 1,231 heterosexual men using Affymetrix single nucleotide polymorphism (SNP) arrays. We identified several SNPs with p < 10-5, including regions of multiple supporting SNPs on chromosomes 13 (minimum p = 7.5 × 10-7) and 14 (p = 4.7 × 10-7). The genes nearest to these peaks have functions plausibly relevant to the development of sexual orientation. On chromosome 13, SLITRK6 is a neurodevelopmental gene mostly expressed in the diencephalon, which contains a region previously reported as differing in size in men by sexual orientation. On chromosome 14, TSHR genetic variants in intron 1 could conceivably help explain past findings relating familial atypical thyroid function and male homosexuality. Furthermore, skewed X chromosome inactivation has been found in the thyroid condition, Graves' disease, as well as in mothers of homosexual men. On pericentromeric chromosome 8 within our previously reported linkage peak, we found support (p = 4.1 × 10-3) for a SNP association previously reported (rs77013977, p = 7.1 × 10-8), with the combined analysis yielding p = 6.7 × 10-9, i.e., a genome-wide significant association.
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Affiliation(s)
- Alan R Sanders
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem Research Institute, Evanston, Illinois, 60201, United States of America.
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois, 60637, United States of America.
| | - Gary W Beecham
- Department of Human Genetics, University of Miami, Miami, Florida, 33136, United States of America
| | - Shengru Guo
- Department of Human Genetics, University of Miami, Miami, Florida, 33136, United States of America
| | - Khytam Dawood
- Department of Psychology, Pennsylvania State University, University Park, Pennsylvania, 16802, United States of America
| | - Gerulf Rieger
- Department of Psychology, University of Essex, Colchester, England, CO4 3SQ, United Kingdom
| | - Judith A Badner
- Department of Psychiatry, Rush University Medical Center, Chicago, Illinois, 60612, United States of America
| | - Elliot S Gershon
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois, 60637, United States of America
| | - Ritesha S Krishnappa
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, Elmhurst, New York, 11373, United States of America
| | - Alana B Kolundzija
- Department of Sociomedical Sciences, Mailman School of Public Health, Columbia University, New York, New York, 10027, United States of America
| | - Jubao Duan
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem Research Institute, Evanston, Illinois, 60201, United States of America
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois, 60637, United States of America
| | - Pablo V Gejman
- Department of Psychiatry and Behavioral Sciences, NorthShore University HealthSystem Research Institute, Evanston, Illinois, 60201, United States of America
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, Illinois, 60637, United States of America
| | - J Michael Bailey
- Department of Psychology, Northwestern University, Evanston, Illinois, 60208, United States of America
| | - Eden R Martin
- Department of Human Genetics, University of Miami, Miami, Florida, 33136, United States of America
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Camperio Ciani A, Battaglia U, Cesare L, Camperio Ciani G, Capiluppi C. Possible Balancing Selection in Human Female Homosexuality. HUMAN NATURE-AN INTERDISCIPLINARY BIOSOCIAL PERSPECTIVE 2017; 29:14-32. [DOI: 10.1007/s12110-017-9309-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Semenyna SW, VanderLaan DP, Petterson LJ, Vasey PL. Familial Patterning and Prevalence of Male Androphilia in Samoa. JOURNAL OF SEX RESEARCH 2017; 54:1077-1084. [PMID: 27593894 DOI: 10.1080/00224499.2016.1218416] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Previous research established that male androphilia (i.e., sexual arousal and attraction to adult males) clusters in families. Some studies find that male androphilia clusters in both the paternal and maternal lines, while others find that it clusters only in the latter. Most of the research investigating the familial nature of male androphilia has taken place in Western cultural contexts that are problematic for such research because they are characterized by low fertility. To address this, our previous work has examined familial patterning of male androphilia in Samoa, a high-fertility population in which androphilic males are readily identified due to their public status as fa'afafine (a third gender category). Building on this work, the present study replicated the familial nature of male androphilia in Samoa using a sample size that was ~122% larger than the one we previously employed (N = 382, M ±SD age: 29.72 years ±10.16). Samoan fa'afafine had significantly more fa'afafine relatives in their maternal and paternal lines compared to Samoan gynephilic males (p < .001). The prevalence of male androphilia was equivalent across both the paternal and maternal lines (all p > .15). The revised prevalence estimate of male androphilia in Samoa falls between 0.61% and 3.51%.
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Affiliation(s)
| | - Doug P VanderLaan
- b Department of Psychology, University of Toronto Mississauga; Underserved Populations Research Program, Child, Youth and Family Division , Centre for Addiction and Mental Health
| | | | - Paul L Vasey
- a Department of Psychology , University of Lethbridge
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Howard RM, Perilloux C. Is mating psychology most closely tied to biological sex or preferred partner's sex? PERSONALITY AND INDIVIDUAL DIFFERENCES 2017. [DOI: 10.1016/j.paid.2016.05.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Balthazart J, Court L. Human Sexual Orientation: The Importance of Evidentiary Convergence. ARCHIVES OF SEXUAL BEHAVIOR 2017; 46:1595-1600. [PMID: 28500563 PMCID: PMC5532062 DOI: 10.1007/s10508-017-0997-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 05/02/2017] [Indexed: 05/26/2023]
Affiliation(s)
- Jacques Balthazart
- GIGA Neurosciences, University of Liège, 15 Avenue Hippocrate, 4000, Liège, Belgium.
| | - Lucas Court
- GIGA Neurosciences, University of Liège, 15 Avenue Hippocrate, 4000, Liège, Belgium
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Breedlove SM. Prenatal Influences on Human Sexual Orientation: Expectations versus Data. ARCHIVES OF SEXUAL BEHAVIOR 2017; 46:1583-1592. [PMID: 28176027 PMCID: PMC5786378 DOI: 10.1007/s10508-016-0904-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 11/10/2016] [Accepted: 11/13/2016] [Indexed: 05/12/2023]
Abstract
In non-human vertebrate species, sexual differentiation of the brain is primarily driven by androgens such as testosterone organizing the brains of males in a masculine fashion early in life, while the lower levels of androgen in developing females organize their brains in a feminine fashion. These principles may be relevant to the development of sexual orientation in humans, because retrospective markers of prenatal androgen exposure, namely digit ratios and otoacoustic emissions, indicate that lesbians, on average, were exposed to greater prenatal androgen than were straight women. Thus, the even greater levels of prenatal androgen exposure experienced by fetal males may explain why the vast majority of them grow up to be attracted to women. However, the same markers indicate no significant differences between gay and straight men in terms of average prenatal androgen exposure, so the variance in orientation in men cannot be accounted for by variance in prenatal androgen exposure, but may be due to variance in response to prenatal androgens. These data contradict several popular notions about human sexual orientation. Sexual orientation in women is said to be fluid, sometimes implying that only social influences in adulthood are at work, yet the data indicate prenatal influences matter as well. Gay men are widely perceived as under-masculinized, yet the data indicate they are exposed to as much prenatal androgen as straight men. There is growing sentiment to reject "binary" conceptions of human sexual orientations, to emphasize instead a spectrum of orientations. Yet the data indicate that human sexual orientation is sufficiently polarized that groups of lesbians, on average, show evidence of greater prenatal androgen exposure than groups of straight women, while groups of gay men have, on average, a greater proportion of brothers among their older siblings than do straight men.
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Affiliation(s)
- S Marc Breedlove
- Neuroscience Program and Departments of Psychology, Integrative Biology, Michigan State University, 293 Farm Lane, Giltner Hall Room 108, East Lansing, MI, 48824-1110, USA.
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