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Odintsova VV, van Dongen J, van Beijsterveldt CEM, Ligthart L, Willemsen G, de Geus EJC, Dolan CV, Boomsma DI. Handedness and 23 Early Life Characteristics in 37,495 Dutch Twins. Twin Res Hum Genet 2023; 26:199-208. [PMID: 37448258 DOI: 10.1017/thg.2023.23] [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] [Indexed: 07/15/2023]
Abstract
In studies of singletons, a range of early-life characteristics have been reported to be associated with handedness, but some of these associations have failed to replicate. We examined associations between 23 early life characteristics with handedness in a large sample of 37,495 5-year-old twins. We considered three definitions of handedness: left-handedness (LH), mixed-handedness (MH), and non-right-handedness (NRH). Our main aim was to test whether the associations with sex, birth weight, gestational age, and season of birth - as reported in singletons - replicate in twins, and to examine twin-specific variables, including zygosity, chorionicity, birth order, and intertwin delivery time. Compared to previously published data from adults born as singletons (7.23%), the prevalence of NRH was higher in both twins (16.19%) and their parents (15.09%). In the twins, LH and NRH were associated with parents' LH. Male sex and lower gestational age were associated with NRH, and LH was associated with not being breastfed. MH was related to neurodevelopmental delays and higher externalizing problems later in childhood. Other previously reported associations were not replicated, and no twin-specific characteristics were related to handedness. These results emphasize the importance of considering multiple definitions of handedness and indicate a small number of replicated associations across studies.
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Affiliation(s)
- Veronika V Odintsova
- Department of Biological Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development (AR&D) Research institute, Amsterdam, The Netherlands
| | - Jenny van Dongen
- Department of Biological Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development (AR&D) Research institute, Amsterdam, The Netherlands
| | | | - Lannie Ligthart
- Department of Biological Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
| | - Gonneke Willemsen
- Department of Biological Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
| | - Eco J C de Geus
- Department of Biological Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
| | - Conor V Dolan
- Department of Biological Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
| | - Dorret I Boomsma
- Department of Biological Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development (AR&D) Research institute, Amsterdam, The Netherlands
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Saari TT, Vuoksimaa E. The role of hand preference in cognition and neuropsychiatric symptoms in neurodegenerative diseases. Brain Commun 2023; 5:fcad137. [PMID: 37265598 PMCID: PMC10231800 DOI: 10.1093/braincomms/fcad137] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/09/2023] [Accepted: 04/21/2023] [Indexed: 06/03/2023] Open
Abstract
Handedness has been shown to be associated with genetic variation involving brain development and neuropsychiatric diseases. Whether handedness plays a role in clinical phenotypes of common neurodegenerative diseases has not been extensively studied. This study used the National Alzheimer's Coordinating Center database to examine whether self-reported handedness was associated with neuropsychological performance and neuropsychiatric symptoms in cognitively unimpaired individuals (n = 17 670), individuals with Alzheimer's disease (n = 10 709), behavioural variant frontotemporal dementia (n = 1132) or dementia with Lewy bodies (n = 637). Of the sample, 8% were left-handed, and 2% were ambidextrous. There were small differences in the handedness distributions across the cognitively unimpaired, Alzheimer's disease, behavioural variant frontotemporal dementia and dementia with Lewy bodies groups (7.2-9.5% left-handed and 0.9-2.2% ambidextrous). After adjusting for age, gender and education, we found faster performance in Trail Making Test A in cognitively unimpaired non-right-handers (ambidextrous and left-handed) compared with right-handers. Excluding ambidextrous individuals, the left-handed cognitively unimpaired individuals had faster Trail Making Test A performance and better Number Span Forward performance than right-handers. Overall, handedness had no effects on most neuropsychological tests and none on neuropsychiatric symptoms. Handedness effect on Trail Making Test A in the cognitively unimpaired is likely to stem from test artefacts rather than a robust difference in cognitive performance. In conclusion, handedness does not appear to affect neuropsychological performance or neuropsychiatric symptoms in common neurodegenerative diseases.
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Affiliation(s)
- Toni T Saari
- Brain Research Unit, Department of Neurology, University of Eastern Finland, Kuopio 70210, Finland
- Department of Neurology, NeuroCenter, Kuopio University Hospital, Kuopio 70210, Finland
- Institute for Molecular Medicine Finland (FIMM), HiLIFE, University of Helsinki, Helsinki 00290, Finland
| | - Eero Vuoksimaa
- Institute for Molecular Medicine Finland (FIMM), HiLIFE, University of Helsinki, Helsinki 00290, Finland
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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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4
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Richardson T. No association between adult sex steroids and hand preference in humans. Am J Hum Biol 2021; 34:e23605. [PMID: 33949024 DOI: 10.1002/ajhb.23605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 03/26/2021] [Accepted: 03/27/2021] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND There is ongoing debate about the effects of hormones on the lateralization of the developing brain. In humans, there are conflicting theories of how testosterone during development should affect lateralization. Empirical studies linking prenatal and postnatal testosterone levels to hand preference (a proxy for lateralization) are similarly mixed. Links between hand preference and health may also suggest a mediating role of steroid hormones such as testosterone and estradiol. Studies to date of adult steroid hormones and handedness have been hindered by samples that contain small numbers of non-right-handers. RESULTS In the largest study of the phenomenon to date, I find that the testosterone (n = 7290) and estradiol (n = 3700) levels of left- and mixed-handed adults are no different to those of right-handers. All Bayesian 95% highest density intervals contained 0. DISCUSSION AND CONCLUSIONS The results have implications for studies that show elevated risk of hormonal-related mental and physical disorders in left-handed individuals.
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Affiliation(s)
- Thomas Richardson
- School of Earth and Environmental Sciences, The University of Manchester, Manchester, UK
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Richards G, Beking T, Kreukels BPC, Geuze RH, Beaton AA, Groothuis T. An examination of the influence of prenatal sex hormones on handedness: Literature review and amniotic fluid data. Horm Behav 2021; 129:104929. [PMID: 33454315 DOI: 10.1016/j.yhbeh.2021.104929] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 12/30/2020] [Accepted: 12/31/2020] [Indexed: 01/27/2023]
Abstract
Competing theories have posited roles for foetal androgen exposure in the development of human handedness. However, due to practical and ethical considerations, few studies have used hormonal measures to examine this possibility. The current paper reviews this literature and reveals a generally inconsistent pattern of results. We also present data from a longitudinal study of prenatal sex hormone exposure and subsequent handedness. More specifically, we examine correlations between testosterone and estradiol measured from second trimester amniotic fluid and hand preference (Dutch language version of the Edinburgh Handedness Inventory) and hand skill asymmetry (pegboard task) measured at 15 years of age. Prenatal sex hormone exposure was not associated with the direction of hand preference in either males or females. However, in females, high levels of prenatal testosterone were associated with weaker lateralisation of hand skill, and high levels of prenatal estradiol were associated with weaker hand preference. In addition, high levels of prenatal testosterone were associated with increased task duration (i.e., slow hand speed) for the right and left hands of males. The pattern of results observed here is not entirely consistent with any of the main theories linking sex hormones with handedness, suggesting that an association between these variables may be more complex than initially thought.
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Affiliation(s)
- Gareth Richards
- Newcastle University, School of Psychology, Ridley Building 1, Queen Victoria Road, Newcastle upon Tyne NE1 7RU, UK; University of Cambridge, Autism Research Centre, Department of Psychiatry, Douglas House, 18b Trumpington Road, Cambridge CB2 8AH, UK.
| | - Tess Beking
- University of Groningen, Faculty of Behavioural and Social Sciences, Department Clinical & Developmental Neuropsychology, Grote Kruisstraat 2/1, 9712 TS Groningen, the Netherlands; Amsterdam University Medical Center, location VUmc, Department of Medical Psychology, Center of Expertise on Gender Dysphoria, PO Box 7057, 1007 MB Amsterdam, the Netherlands; University of Groningen, Groningen Institute for Evolutionary Life Sciences, Nijenborgh 7, 9747 AG Groningen, the Netherlands
| | - Baudewijntje P C Kreukels
- Amsterdam University Medical Center, location VUmc, Department of Medical Psychology, Center of Expertise on Gender Dysphoria, PO Box 7057, 1007 MB Amsterdam, the Netherlands
| | - Reint H Geuze
- University of Groningen, Faculty of Behavioural and Social Sciences, Department Clinical & Developmental Neuropsychology, Grote Kruisstraat 2/1, 9712 TS Groningen, the Netherlands
| | - Alan A Beaton
- Swansea University, Department of Psychology, School of Human & Health Sciences, Swansea SA2 8PP, UK; Aberystwyth University, Department of Psychology, Aberystwyth SY23 3UX, UK
| | - Ton Groothuis
- University of Groningen, Groningen Institute for Evolutionary Life Sciences, Nijenborgh 7, 9747 AG Groningen, the Netherlands
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Richards G, Medland SE, Beaton AA. Digit ratio (2D:4D) and handedness: A meta-analysis of the available literature. Laterality 2021; 26:421-484. [PMID: 33517845 DOI: 10.1080/1357650x.2020.1862141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The Geschwind-Behan-Galaburda and sexual differentiation models predict an association between elevated foetal androgen exposure and left-handedness whereas the callosal hypothesis predicts the opposite. We present a meta-analysis of correlations between handedness and digit ratio (2D:4D), a putative marker of prenatal testosterone. Left-handedness predicted low (male-typical) right-hand digit ratio (R2D:4D), high (female-typical) left-hand digit ratio (L2D:4D), and low R2D:4D-L2D:4D directional asymmetry (D[R-L]). Effect sizes were extremely small and not moderated by sex or method of measuring handedness or 2D:4D. The same general pattern was observed after excluding the very large study (110,329 males, 90,412 females) of Manning and Peters ([2009]. Digit ratio (2D:4D) and hand preference for writing in the BBC Internet Study. Laterality: Asymmetries of Body, Brain and Cognition, 14(5), 528-540. doi:10.1080/13576500802637872); however, no significant effects for R2D:4D were observed once these samples were removed. The results do not confirm any theory linking prenatal androgens with handedness, so we speculate they instead reflect the mechanical action of writing causing subtle changes in the musculature and/or fat pads of the fingers. Gripping a pen/pencil might cause an increase in 2D relative to 4D (and/or decrease in 4D relative to 2D) resulting in higher ratios on the writing-hand; furthermore, this could differ between left- and right-handers due to writing in the left-to-right direction (as in English) having asymmetrical effects depending on which hand is used.
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Affiliation(s)
- Gareth Richards
- School of Psychology, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK.,Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, UK.,Centre for Research on Play in Education, Development & Learning, Faculty of Education, University of Cambridge, Cambridge, UK
| | - Sarah E Medland
- Psychiatric Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia.,School of Psychology, University of Queensland, St Lucia, Australia.,School of Psychology and Counselling, Queensland University of Technology, Brisbane, Australia
| | - Alan A Beaton
- Department of Psychology, School of Human & Health Sciences, Swansea University, Swansea, UK.,Department of Psychology, Aberystwyth University, Aberystwyth, UK
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Wong NA, Saier MH. The SARS-Coronavirus Infection Cycle: A Survey of Viral Membrane Proteins, Their Functional Interactions and Pathogenesis. Int J Mol Sci 2021; 22:1308. [PMID: 33525632 PMCID: PMC7865831 DOI: 10.3390/ijms22031308] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 02/07/2023] Open
Abstract
Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a novel epidemic strain of Betacoronavirus that is responsible for the current viral pandemic, coronavirus disease 2019 (COVID-19), a global health crisis. Other epidemic Betacoronaviruses include the 2003 SARS-CoV-1 and the 2009 Middle East Respiratory Syndrome Coronavirus (MERS-CoV), the genomes of which, particularly that of SARS-CoV-1, are similar to that of the 2019 SARS-CoV-2. In this extensive review, we document the most recent information on Coronavirus proteins, with emphasis on the membrane proteins in the Coronaviridae family. We include information on their structures, functions, and participation in pathogenesis. While the shared proteins among the different coronaviruses may vary in structure and function, they all seem to be multifunctional, a common theme interconnecting these viruses. Many transmembrane proteins encoded within the SARS-CoV-2 genome play important roles in the infection cycle while others have functions yet to be understood. We compare the various structural and nonstructural proteins within the Coronaviridae family to elucidate potential overlaps and parallels in function, focusing primarily on the transmembrane proteins and their influences on host membrane arrangements, secretory pathways, cellular growth inhibition, cell death and immune responses during the viral replication cycle. We also offer bioinformatic analyses of potential viroporin activities of the membrane proteins and their sequence similarities to the Envelope (E) protein. In the last major part of the review, we discuss complement, stimulation of inflammation, and immune evasion/suppression that leads to CoV-derived severe disease and mortality. The overall pathogenesis and disease progression of CoVs is put into perspective by indicating several stages in the resulting infection process in which both host and antiviral therapies could be targeted to block the viral cycle. Lastly, we discuss the development of adaptive immunity against various structural proteins, indicating specific vulnerable regions in the proteins. We discuss current CoV vaccine development approaches with purified proteins, attenuated viruses and DNA vaccines.
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Affiliation(s)
- Nicholas A. Wong
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA
| | - Milton H. Saier
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, USA
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van Heerwaarde AA, van der Kamp LT, van der Aa NE, de Vries LS, Groenendaal F, Jongmans MJ, Eijsermans RJC, Koopman-Esseboom C, van Haastert ILC, Benders MJNL, Dudink J. Non-right-handedness in children born extremely preterm: Relation to early neuroimaging and long-term neurodevelopment. PLoS One 2020; 15:e0235311. [PMID: 32628734 PMCID: PMC7337339 DOI: 10.1371/journal.pone.0235311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 06/14/2020] [Indexed: 11/18/2022] Open
Abstract
Objective This study aimed to define the prevalence and predictors of non-right-handedness and its link to long-term neurodevelopmental outcome and early neuroimaging in a cohort of children born extremely preterm (<28 weeks gestation). Methods 179 children born extremely preterm admitted to the Neonatal Intensive Care Unit of our tertiary centre from 2006–2013 were included in a prospective longitudinal cohort study. Collected data included perinatal data, demographic characteristics, neurodevelopmental outcome measured by the Bayley Scales of Infant and Toddler Development at 2 years and the Movement Assessment Battery for Children at 5 years, and handedness measured at school age (4–8 years). Magnetic resonance imaging performed at term-equivalent age was used to study overt brain injury. Diffusion tensor imaging scans were analysed using tract-based spatial statistics to assess white matter microstructure in relation to handedness and neurodevelopmental outcome. Results The prevalence of non-right-handedness in our cohort was 22.9%, compared to 12% in the general population. Weaker fine motor skills at 2 years and paternal non-right-handedness were significantly associated with non-right-handedness. Both overt brain injury and fractional anisotropy of white matter structures on diffusion tensor images were not related to handedness. Fractional anisotropy measurements showed significant associations with neurodevelopmental outcome. Conclusions Our data show that non-right-handedness in children born extremely preterm occurs almost twice as frequently as in the general population. In the studied population, non-right-handedness is associated with weaker fine motor skills and paternal non-right-handedness, but not with overt brain injury or microstructural brain development on early magnetic resonance imaging.
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Affiliation(s)
- Alise A. van Heerwaarde
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
- * E-mail:
| | - Laura T. van der Kamp
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Niek E. van der Aa
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Linda S. de Vries
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Floris Groenendaal
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Marian J. Jongmans
- Department of Paediatric Psychology, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Rian J. C. Eijsermans
- Department of Paediatric Physical Therapy and Exercise Physiology, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Corine Koopman-Esseboom
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Inge-Lot C. van Haastert
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Manon J. N. L. Benders
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Jeroen Dudink
- Department of Neonatology, Wilhelmina Children’s Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, The Netherlands
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Zheng M, McBride C, Ho CSH, Chan JKC, Choy KW, Paracchini S. Prevalence and heritability of handedness in a Hong Kong Chinese twin and singleton sample. BMC Psychol 2020; 8:37. [PMID: 32321583 PMCID: PMC7178737 DOI: 10.1186/s40359-020-00401-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Accepted: 03/31/2020] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Left-handedness prevalence has been consistently reported at around 10% with heritability estimates at around 25%. Higher left-handedness prevalence has been reported in males and in twins. Lower prevalence has been reported in Asia, but it remains unclear whether this is due to biological or cultural factors. Most studies are based on samples with European ethnicities and using the preferred hand for writing as key assessment. Here, we investigated handedness in a sample of Chinese school children in Hong Kong, including 426 singletons and 205 pairs of twins, using both the Edinburgh Handedness Inventory and Pegboard Task. RESULTS Based on a binary definition of writing hand, we found a higher prevalence of left-handedness (8%) than what was previously reported in Asian datasets. We found no evidence of increased left-handedness in twins, but our results were in line with previous findings showing that males have a higher tendency to be left-handed than females. Heritability was similar for both hand preference (21%) and laterality indexes (22%). However, these two handedness measures present only a moderate correlation (.42) and appear to be underpinned by different genetic factors. CONCLUSION In summary, we report new reference data for an ethnic group usually underrepresented in the literature. Our heritability analysis supports the idea that different measures will capture different components of handedness and, as a consequence, datasets assessed with heterogeneous criteria are not easily combined or compared.
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Affiliation(s)
- Mo Zheng
- Department of Psychology, The Chinese University of Hong Kong, Hong Kong, China
| | - Catherine McBride
- Department of Psychology, The Chinese University of Hong Kong, Hong Kong, China
| | - Connie Suk-Han Ho
- Department of Psychology, The University of Hong Kong, Hong Kong, China
| | | | - Kwong Wai Choy
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
| | - Silvia Paracchini
- School of Medicine, University of St Andrews, St. Andrews, Scotland.
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Opposite-sex and same-sex twin studies of physiological, cognitive and behavioral traits. Neurosci Biobehav Rev 2019; 108:322-340. [PMID: 31711815 DOI: 10.1016/j.neubiorev.2019.11.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 09/30/2019] [Accepted: 11/07/2019] [Indexed: 01/12/2023]
Abstract
A scientific interest in opposite-sex (OS) twins comes from animal studies showing hormone transfer between fetuses in utero. A parallel effect in humans may occur, especially for OS females who may be exposed to androgens, in particular testosterone, from the male co-twin. Conversely, OS males may be exposed to lower levels of prenatal testosterone than do same-sex (SS) males. In this special issue, we reviewed published studies investigating potential differences between OS and SS twins in physiological, cognitive and behavioral traits focusing on the Twin Testosterone Transfer (TTT) hypothesis. Sixty articles fulfilled the eligibility criteria including 23 studies published since the review by Tapp et al. (2011). In general, studies of cognition are conflicting, but it is the phenotype for which most support for the TTT hypothesis is found. Less consistent evidence has been found regarding physiological and behavioral traits. We hope that this special issue will stimulate a discussion about how an investigation of the TTT hypothesis should continue in future research.
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11
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Perret M. Litter sex composition affects first reproduction in female grey mouse lemurs (Microcebus murinus). Physiol Behav 2019; 208:112575. [DOI: 10.1016/j.physbeh.2019.112575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 01/25/2023]
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12
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A large-scale population study of early life factors influencing left-handedness. Sci Rep 2019; 9:584. [PMID: 30679750 PMCID: PMC6345846 DOI: 10.1038/s41598-018-37423-8] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/29/2018] [Indexed: 12/27/2022] Open
Abstract
Hand preference is a conspicuous variation in human behaviour, with a worldwide proportion of around 90% of people preferring to use the right hand for many tasks, and 10% the left hand. We used the large cohort of the UK biobank (~500,000 participants) to study possible relations between early life factors and adult hand preference. The probability of being left-handed was affected by the year and location of birth, likely due to cultural effects. In addition, hand preference was affected by birthweight, being part of a multiple birth, season of birth, breastfeeding, and sex, with each effect remaining significant after accounting for all others. Analysis of genome-wide genotype data showed that left-handedness was very weakly heritable, but shared no genetic basis with birthweight. Although on average left-handers and right-handers differed for a number of early life factors, all together these factors had only a minimal predictive value for individual hand preference.
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Abstract
The mechanisms behind handedness formation in humans are still poorly understood. Very low birthweight is associated with higher odds of left-handedness, but whether this is due to low birthweight itself or premature birth is unknown. Handedness has also been linked to development, but the role of birthweight behind this association is unclear. Knowing that birthweight is lower in multiple births, triplets being about 1.5 kg lighter in comparison with singletons, and that multiples have a higher prevalence of left-handedness than singletons, we studied the association between birthweight and handedness in two large samples consisting exclusively of triplets from Japan (n = 1,305) and the Netherlands (n = 947). In both samples, left-handers had significantly lower birthweight (Japanese mean = 1,599 g [95% confidence interval (CI): 1,526-1,672 g]; Dutch mean = 1,794 g [95% CI: 1,709-1,879 g]) compared with right-handers (Japanese mean = 1,727 g [95% CI: 1,699-1,755 g]; Dutch mean = 1,903 g [95% CI: 1,867-1,938 g]). Within-family and between-family analyses both suggested that left-handedness is associated with lower birthweight, also when fully controlling for gestational age. Left-handers also had significantly delayed motor development and smaller infant head circumference compared with right-handers, but these associations diluted and became nonsignificant when controlling for birthweight. Our study in triplets provides evidence for the link between low birthweight and left-handedness. Our results also suggest that developmental differences between left- and right-handers are due to a shared etiology associated with low birthweight.
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Miller B, Peeri NC, Nabors LB, Creed JH, Thompson ZJ, Rozmeski CM, LaRocca RV, Chowdhary S, Olson JJ, Thompson RC, Egan KM. Handedness and the risk of glioma. J Neurooncol 2018; 137:639-644. [PMID: 29332185 DOI: 10.1007/s11060-018-2759-y] [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: 09/15/2017] [Accepted: 01/05/2018] [Indexed: 12/01/2022]
Abstract
Gliomas are the most common type of malignant primary brain tumor and few risk factors have been linked to their development. Handedness has been associated with several pathologic neurological conditions such as schizophrenia, autism, and epilepsy, but few studies have evaluated a connection between handedness and risk of glioma. In this study, we examined the relationship between handedness and glioma risk in a large case-control study (1849 glioma cases and 1354 healthy controls) and a prospective cohort study (326,475 subjects with 375 incident gliomas). In the case-control study, we found a significant inverse association between left handedness and glioma risk, with left-handed persons exhibiting a 35% reduction in the risk of developing glioma [odds ratio (OR) = 0.65, 95% confidence interval (CI) 0.51-0.83] after adjustment for age, gender, race, education, and state of residence; similar inverse associations were observed for GBM (OR = 0.69, 95% CI 0.52-0.91), and non-GBM (OR = 0.59, 95% CI 0.42-0.82) subgroups. The association was consistent in both males and females, and across age strata, and was observed in both glioblastoma and in lower grade tumors. In the prospective cohort study, we found no association between handedness and glioma risk (hazards ratio = 0.92, 95% CI 0.67-1.28) adjusting for age, gender, and race. Further studies on this association may help to elucidate mechanisms of pathogenesis in glioma.
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Affiliation(s)
- Briana Miller
- Neuro-Oncology Program, University of Alabama at Birmingham, FOT 1020, 510 20th St. South, Birmingham, AL, 35294, USA
| | - Noah C Peeri
- Department of Cancer Epidemiology, H. Lee Moffitt Cancer Center & Research Institute, 12902 Magnolia Drive, Tampa, FL, 33612-9416, USA
| | - Louis Burt Nabors
- Neuro-Oncology Program, University of Alabama at Birmingham, FOT 1020, 510 20th St. South, Birmingham, AL, 35294, USA
| | - Jordan H Creed
- Department of Cancer Epidemiology, H. Lee Moffitt Cancer Center & Research Institute, 12902 Magnolia Drive, Tampa, FL, 33612-9416, USA
| | - Zachary J Thompson
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, 12902 Magnolia Drive, Tampa, FL, 33612, USA
| | - Carrie M Rozmeski
- Department of Cancer Epidemiology, H. Lee Moffitt Cancer Center & Research Institute, 12902 Magnolia Drive, Tampa, FL, 33612-9416, USA
| | - Renato V LaRocca
- Norton Cancer Institute, 676 So Floyd St., Louisville, KY, 40202, USA
| | - Sajeel Chowdhary
- Neuro-Oncology Program, Lynn Cancer Institute, 701 NW 13th Street, Boca Raton, FL, 33486, USA
| | - Jeffrey J Olson
- Department of Neurosurgery, Emory University School of Medicine, 1365-B Clifton Rd., NE, Ste. 2200, Atlanta, GA, 30322, USA
| | - Reid C Thompson
- Department of Neurological Surgery, Vanderbilt University Medical Center, 691 Preston Building, Nashville, TN, 37232, USA
| | - Kathleen M Egan
- Department of Cancer Epidemiology, H. Lee Moffitt Cancer Center & Research Institute, 12902 Magnolia Drive, Tampa, FL, 33612-9416, USA.
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15
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Schmitz J, Metz GA, Güntürkün O, Ocklenburg S. Beyond the genome—Towards an epigenetic understanding of handedness ontogenesis. Prog Neurobiol 2017; 159:69-89. [DOI: 10.1016/j.pneurobio.2017.10.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 09/18/2017] [Accepted: 10/26/2017] [Indexed: 12/13/2022]
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Papadatou-Pastou M, Martin M. Cerebral laterality for language is related to adult salivary testosterone levels but not digit ratio (2D:4D) in men: A functional transcranial Doppler ultrasound study. BRAIN AND LANGUAGE 2017; 166:52-62. [PMID: 28088127 DOI: 10.1016/j.bandl.2016.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 11/07/2016] [Accepted: 12/12/2016] [Indexed: 06/06/2023]
Abstract
The adequacy of three competing theories of hormonal effects on cerebral laterality are compared using functional transcranial Doppler sonography (fTCD). Thirty-three adult males participated in the study (21 left-handers). Cerebral lateralization was measured by fTCD using an extensively validated word generation task. Adult salivary testosterone (T) and cortisol (C) concentrations were measured by luminescence immunoassay and prenatal T exposure was indirectly estimated by the somatic marker of 2nd to 4th digit length ratio (2D:4D). A significant quadratic relationship between degree of cerebral laterality for language and adult T concentrations was observed, with enhanced T levels for strong left hemisphere dominance and strong right hemisphere dominance. No systematic effects on laterality were found for cortisol or 2D:4D. Findings suggest that higher levels of T are associated with a relatively attenuated degree of interhemispheric sharing of linguistic information, providing support for the callosal and the sexual differentiation hypotheses rather than the Geschwind, Behan and Galaburda (GBG) hypothesis.
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Affiliation(s)
- Marietta Papadatou-Pastou
- Cognition and Health Research Group, Department of Experimental Psychology, University of Oxford, 9 South Parks Road, Oxford OX1 3UD, UK.
| | - Maryanne Martin
- Cognition and Health Research Group, Department of Experimental Psychology, University of Oxford, 9 South Parks Road, Oxford OX1 3UD, UK.
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Swift-Gallant A, Coome LA, Monks DA, VanderLaan DP. Handedness is a biomarker of variation in anal sex role behavior and Recalled Childhood Gender Nonconformity among gay men. PLoS One 2017; 12:e0170241. [PMID: 28234947 PMCID: PMC5325203 DOI: 10.1371/journal.pone.0170241] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 12/30/2016] [Indexed: 11/24/2022] Open
Abstract
Developmental theories of the biological basis of sexual orientation suggest that sexually differentiated psychological and behavioural traits should be linked with sexual orientation. Subgroups of gay men delineated by anal sex roles differ according to at least one such trait: gender expression. The present study assessed the hypothesis that handedness, a biologically determined sexually differentiated trait, corresponds to differences in subgroups of gay men based on anal sex role. Furthermore, it assessed whether handedness mediates the association between gender nonconformity and male sexual orientation. Straight and gay men (N = 333) completed the Edinburgh Inventory of Handedness and the Recalled Childhood Gender Nonconformity Scale. Gay men also completed measures of anal sex role preference. As in previous studies, gay men showed greater non-right-handedness and gender nonconformity than straight men. Also, among gay men, bottoms/versatiles (i.e., gay men who take a receptive anal sex role, or who take on both a receptive and insertive anal sex role) were more gender-nonconforming than tops (i.e., gay men who take an insertive anal sex role). In support of the hypothesis, bottoms/versatiles were more non-right-handed than tops and handedness mediated the male sexual orientation and anal sex role differences in Recalled Childhood Gender Nonconformity. Together, these findings suggest that developmental processes linked to handedness underpin variation among men in sexual orientation and gender nonconformity as well as variation among subgroups of gay men that are delineated by anal sex roles.
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Affiliation(s)
- Ashlyn Swift-Gallant
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
- Department of Psychology, University of Toronto at Mississauga, Mississauga, Ontario, Canada
| | - Lindsay A. Coome
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
- Department of Psychology, University of Toronto at Mississauga, Mississauga, Ontario, Canada
| | - D. Ashley Monks
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
- Department of Psychology, University of Toronto at Mississauga, Mississauga, Ontario, Canada
| | - Doug P. VanderLaan
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
- Department of Psychology, University of Toronto at Mississauga, Mississauga, Ontario, Canada
- Child, Youth and Family Division, Underserved Populations Research Program, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada
- * E-mail:
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Papadatou-Pastou M, Martin M, Mohr C. Salivary testosterone levels are unrelated to handedness or cerebral lateralization for language. Laterality 2016; 22:123-156. [DOI: 10.1080/1357650x.2016.1149485] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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19
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Left with Raging Hormones. Laterality 2016. [DOI: 10.1016/b978-0-12-801239-0.00005-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Bonnet F, Affret A, Boutron-Ruault MC, Balkau B, Clavel-Chapelon F, Fagherazzi G. Association Between Handedness and Type 2 Diabetes: The E3N Study. Diabetes Care 2015; 38:e199. [PMID: 26486188 DOI: 10.2337/dc15-1669] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/07/2015] [Indexed: 02/03/2023]
Affiliation(s)
- Fabrice Bonnet
- INSERM U1018, Center for Research in Epidemiology and Population Health, Villejuif, France Paris-South University, Villejuif, France Centre Hospitalier Universitaire de Rennes, University Rennes 1, Rennes, France
| | - Aurélie Affret
- INSERM U1018, Center for Research in Epidemiology and Population Health, Villejuif, France Paris-South University, Villejuif, France
| | - Marie-Christine Boutron-Ruault
- INSERM U1018, Center for Research in Epidemiology and Population Health, Villejuif, France Paris-South University, Villejuif, France
| | - Beverley Balkau
- INSERM U1018, Center for Research in Epidemiology and Population Health, Villejuif, France Paris-South University, Villejuif, France University of Versailles Saint-Quentin-en-Yvelines, Versailles, France
| | - Françoise Clavel-Chapelon
- INSERM U1018, Center for Research in Epidemiology and Population Health, Villejuif, France Paris-South University, Villejuif, France
| | - Guy Fagherazzi
- INSERM U1018, Center for Research in Epidemiology and Population Health, Villejuif, France Paris-South University, Villejuif, France
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21
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Hampson E. The development of hand preference and dichotic language lateralization in males and females with congenital adrenal hyperplasia. Laterality 2015; 21:415-432. [DOI: 10.1080/1357650x.2015.1102924] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Buoli M, Croci R. Testosterone, fraternal birth order, and homosexuality: comment on Kishida and Rahman (2015). ARCHIVES OF SEXUAL BEHAVIOR 2015; 44:1755-1756. [PMID: 26076927 DOI: 10.1007/s10508-015-0578-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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Higher Prevalence of Left-Handedness in Twins? Not After Controlling Birth Time Confounders. Twin Res Hum Genet 2015; 18:526-32. [DOI: 10.1017/thg.2015.53] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Pregnancy- and birth-related factors may have an effect on handedness. Compared with singletons, twins have a lower birth weight, shorter gestational age, and are at higher risk for birth complications. We tested whether the prevalence of left-handedness is higher among twins than singletons, and if so, whether that difference is fully explained by pregnancy and birth-related differences between twins and singletons. We analyzed Finnish population-based datasets; included were 8,786 twins and 5,892 singletons with information on birth weight (n = 12,381), Apgar scores (n = 11,129), and gestational age (n = 11,811). Two twin cohorts were involved: FinnTwin12 included twins born during 1983–1987, and FinnTwin16 included twins born during 1974–1979. We had two comparison groups of singletons: 4,101 individuals born during 1986–1988 and enrolled in the Helsinki Ultrasound Trial, and 1,791 individuals who were partners of FinnTwin16 twins. We used logistic regression models with writing hand as the outcome for comparison and evaluating effects of covariates. Left-handedness was more common in twins (9.67%) than in singletons (8.27%; p = .004). However, Apgar scores were associated with handedness, and after controlling for covariates, we found no difference in the prevalence of left-handedness between twins and singletons. Increased left-handedness among twins, often reported by others, was evident in our data, but only among our older twin cohorts, and that association disappeared after removing effects of perinatal covariates.
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Kishida M, Rahman Q. Fraternal Birth Order and Extreme Right-Handedness as Predictors of Sexual Orientation and Gender Nonconformity in Men. ARCHIVES OF SEXUAL BEHAVIOR 2015; 44:1493-1501. [PMID: 25663238 DOI: 10.1007/s10508-014-0474-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 12/01/2014] [Accepted: 12/06/2014] [Indexed: 06/04/2023]
Abstract
The present study explored whether there were relationships between number of older brothers, handedness, recalled childhood gender nonconformity (CGN), and sexual orientation in men. We used data from previous British studies conducted in our laboratory (N = 1,011 heterosexual men and 921 gay men). These men had completed measures of demographic variables, number and sex of siblings, CGN, and the Edinburgh Handedness Inventory. The results did not replicate the fraternal birth order effect. However, gay men had fewer "other siblings" than heterosexual men (even after controlling for the stopping-rule and family size). In a sub-sample (425 gay men and 478 heterosexual men) with data available on both sibling sex composition and handedness scores, gay men were found to show a significantly greater likelihood of extreme right-handedness and non-right-handedness compared to heterosexual men. There were no significant effects of sibling sex composition in this sub-sample. In a further sub-sample (N = 487) with data available on sibling sex composition, handedness, and CGN, we found that men with feminine scores on CGN were more extremely right-handed and had fewer other-siblings compared to masculine scoring men. Mediation analysis revealed that handedness was associated with sexual orientation directly and also indirectly through the mediating factor of CGN. We were unable to replicate the fraternal birth order effect in our archived dataset but there was evidence for a relationship among handedness, sexual orientation, and CGN. These data help narrow down the number of possible neurodevelopmental pathways leading to variations in male sexual orientation.
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Affiliation(s)
- Mariana Kishida
- Department of Psychology, Institute of Psychiatry, King's College London, 5th Floor, Bermondsey Wing, Guy's Hospital Campus, London, SE1 9RT, UK,
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25
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Benetos A, Dalgård C, Labat C, Kark JD, Verhulst S, Christensen K, Kimura M, Horvath K, Kyvik KO, Aviv A. Sex difference in leukocyte telomere length is ablated in opposite-sex co-twins. Int J Epidemiol 2014; 43:1799-805. [PMID: 25056338 PMCID: PMC4276058 DOI: 10.1093/ije/dyu146] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Background: In eutherian mammals and in humans, the female fetus may be masculinized while sharing the intra-uterine environment with a male fetus. Telomere length (TL), as expressed in leukocytes, is heritable and is longer in women than in men. The main determinant of leukocyte TL (LTL) is LTL at birth. However, LTL is modified by age-dependent attrition. Methods: We studied LTL dynamics (LTL and its attrition) in adult same-sex (monozygotic, n = 268; dizygotic, n = 308) twins and opposite-sex (n = 144) twins. LTL was measured by Southern blots of the terminal restriction fragments. Results: We observed that in same-sex (both monozygotic and dizygotic) twins, as reported in singletons, LTL was longer in females than in males [estimate ± standard error (SE):163 ± 63 bp, P < 0.01]. However, in opposite-sex twins, female LTL was indistinguishable from that of males (−31 ± 52 bp, P = 0.6), whereas male LTL was not affected. Findings were similar when the comparison was restricted to opposite-sex and same-sex dizygotic twins (females relative to males: same-sex: 188 ± 90 bp, P < 0.05; other-sex: −32 ± 64 bp, P = 0.6). Conclusions: These findings are compatible with masculinization of the female fetus in opposite-sex twins. They suggest that the sex difference in LTL, seen in the general population, is largely determined in utero, perhaps by the intrauterine hormonal environment. Further studies in newborn twins are warranted to test this thesis.
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Affiliation(s)
- Athanase Benetos
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, Universi
| | - Christine Dalgård
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
| | - Carlos Labat
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
| | - Jeremy D Kark
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
| | - Simon Verhulst
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
| | - Kaare Christensen
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, Universi
| | - Masayuki Kimura
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
| | - Kent Horvath
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
| | - Kirsten Ohm Kyvik
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
| | - Abraham Aviv
- Département de Médecine Gériatrique, CHU de Nancy, Nancy, France, INSERM, U1116, Vandoeuvre-les-Nancy, France, Université de Lorraine, Nancy, France, Department of Environmental Medicine, University of Southern Denmark, Odense, Denmark, Hebrew University-Hadassah School of Public Health and Community Medicine, Jerusalem, Israel, Centre for Behaviour and Neurosciences, University of Groningen, Groningen, The Netherlands, Danish Twin Registry, University of Southern Denmark, Odense, Denmark, Department of Clinical Genetics and Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark, Center of Human Development and Aging, State University of New Jersey, Newark, NJ, USA and Institute of Regional Health Services Research, University of Southern Denmark and Odense Patient Data Explorative Network (OPEN), Odense University Hospital, Odense, Denmark
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Korsoff P, Bogl LH, Korhonen P, Kangas AJ, Soininen P, Ala-Korpela M, Rose RJ, Kaaja R, Kaprio J. A comparison of anthropometric, metabolic, and reproductive characteristics of young adult women from opposite-sex and same-sex twin pairs. Front Endocrinol (Lausanne) 2014; 5:28. [PMID: 24639667 PMCID: PMC3945783 DOI: 10.3389/fendo.2014.00028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/19/2014] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Prenatal exposure to androgens has been linked to masculinization of several traits. We aimed to determine whether putative female intra-uterine exposure to androgens influences anthropometric, metabolic, and reproductive parameters using a twin design. METHODS Two cohorts of Finnish twins born in 1975-1979 and 1983-1987 formed the basis for the longitudinal FinnTwin16 (FT16) and FinnTwin12 (FT12) studies. Self-reported anthropometric characteristics, disease status, and reproductive history were compared between 679 same-sex (SS) and 789 opposite-sex (OS) female twins (mean age ± SD: 34 ± 1.1) from the wave 5 of data collection in FT16. Serum lipid and lipoprotein subclass concentrations measured by nuclear magnetic resonance spectroscopy were compared in 226 SS and 169 OS female twins (mean age ± SD: 24 ± 2.1) from the wave 4 of data collection in FT12 and FT16. RESULTS Anthropometric measures, the prevalence of hypertension and diabetes mellitus type 2 did not differ significantly between females from SS and OS twin pairs at age 34. Similarly, the prevalence of infertility, age at first pregnancy and number of induced and spontaneous abortions did not differ significantly between these two groups of women. The serum lipid and lipoprotein profile did not differ between females from SS and OS twins at age 24. CONCLUSION We found no evidence that androgen overexposure of the female fetus affects obesity, metabolic profile, or reproductive health in young adult females. However, these results do not exclude the possibility that prenatal androgen exposure in females could be adversely associated with these phenotypes later in life.
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Affiliation(s)
| | - Leonie H. Bogl
- Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Päivi Korhonen
- Satakunta Central Hospital, Pori and University of Turku, Turku, Finland
| | - Antti J. Kangas
- Computational Medicine, Institute of Health Sciences, Faculty of Medicine, University of Oulu, Oulu, Finland
| | - Pasi Soininen
- Computational Medicine, Institute of Health Sciences, Faculty of Medicine, University of Oulu, Oulu, Finland
- NMR Metabolomics Laboratory, School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Mika Ala-Korpela
- Computational Medicine, Institute of Health Sciences, Faculty of Medicine, University of Oulu, Oulu, Finland
- NMR Metabolomics Laboratory, School of Pharmacy, University of Eastern Finland, Kuopio, Finland
- Oulu University Hospital, Oulu, Finland
- Computational Medicine, Medical Research Council Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Richard J. Rose
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, USA
| | - Risto Kaaja
- Satakunta Central Hospital, Pori and University of Turku, Turku, Finland
| | - Jaakko Kaprio
- Department of Public Health, University of Helsinki, Helsinki, Finland
- Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland
- Institute for Molecular Medicine FIMM, Helsinki, Finland
- *Correspondence: Jaakko Kaprio, Department of Public Health, University of Helsinki, PO Box 41, Helsinki, Finland e-mail:
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27
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Floris DL, Chura LR, Holt RJ, Suckling J, Bullmore ET, Baron-Cohen S, Spencer MD. Psychological correlates of handedness and corpus callosum asymmetry in autism: the left hemisphere dysfunction theory revisited. J Autism Dev Disord 2013; 43:1758-72. [PMID: 23179344 PMCID: PMC3708282 DOI: 10.1007/s10803-012-1720-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Rightward cerebral lateralization has been suggested to be involved in the neuropathology of autism spectrum conditions. We investigated functional and neuroanatomical asymmetry, in terms of handedness and corpus callosum measurements in male adolescents with autism, their unaffected siblings and controls, and their associations with executive dysfunction and symptom severity. Adolescents with autism did not differ from controls in functional asymmetry, but neuroanatomically showed the expected pattern of stronger rightward lateralization in the posterior and anterior midbody based on their hand-preference. Measures of symptom severity were related to rightward asymmetry in three subregions (splenium, posterior midbody and rostral body). We found the opposite pattern for the isthmus and rostrum with better cognitive and less severe clinical scores associated with rightward lateralization.
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Affiliation(s)
- Dorothea L. Floris
- />Department of Psychiatry, Autism Research Centre, University of Cambridge, Cambridge, UK
| | - Lindsay R. Chura
- />Department of Psychiatry, Autism Research Centre, University of Cambridge, Cambridge, UK
| | - Rosemary J. Holt
- />Department of Psychiatry, Autism Research Centre, University of Cambridge, Cambridge, UK
| | - John Suckling
- />Department of Psychiatry, Herchel Smith Building for Brain and Mind Sciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Edward T. Bullmore
- />Department of Psychiatry, Herchel Smith Building for Brain and Mind Sciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Simon Baron-Cohen
- />Department of Psychiatry, Autism Research Centre, University of Cambridge, Cambridge, UK
| | - Michael D. Spencer
- />Department of Psychiatry, Autism Research Centre, University of Cambridge, Cambridge, UK
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28
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Lenz B, Müller CP, Kornhuber J. Alcohol dependence in same-sex and opposite-sex twins. J Neural Transm (Vienna) 2012; 119:1561-4. [PMID: 23104613 DOI: 10.1007/s00702-012-0907-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 10/16/2012] [Indexed: 11/24/2022]
Abstract
Males with a female co-twin are more likely to become alcohol-dependent than males with a male co-twin. According to the twin testosterone transfer model, this finding can be interpreted as indirect evidence for a role of prenatal testosterone in alcohol dependence.
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Affiliation(s)
- Bernd Lenz
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Schwabachanlage 6-10, 91054, Erlangen, Germany.
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29
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Vandenberg LN, Colborn T, Hayes TB, Heindel JJ, Jacobs DR, Lee DH, Shioda T, Soto AM, vom Saal FS, Welshons WV, Zoeller RT, Myers JP. Hormones and endocrine-disrupting chemicals: low-dose effects and nonmonotonic dose responses. Endocr Rev 2012; 33:378-455. [PMID: 22419778 PMCID: PMC3365860 DOI: 10.1210/er.2011-1050] [Citation(s) in RCA: 1978] [Impact Index Per Article: 164.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 02/07/2012] [Indexed: 02/08/2023]
Abstract
For decades, studies of endocrine-disrupting chemicals (EDCs) have challenged traditional concepts in toxicology, in particular the dogma of "the dose makes the poison," because EDCs can have effects at low doses that are not predicted by effects at higher doses. Here, we review two major concepts in EDC studies: low dose and nonmonotonicity. Low-dose effects were defined by the National Toxicology Program as those that occur in the range of human exposures or effects observed at doses below those used for traditional toxicological studies. We review the mechanistic data for low-dose effects and use a weight-of-evidence approach to analyze five examples from the EDC literature. Additionally, we explore nonmonotonic dose-response curves, defined as a nonlinear relationship between dose and effect where the slope of the curve changes sign somewhere within the range of doses examined. We provide a detailed discussion of the mechanisms responsible for generating these phenomena, plus hundreds of examples from the cell culture, animal, and epidemiology literature. We illustrate that nonmonotonic responses and low-dose effects are remarkably common in studies of natural hormones and EDCs. Whether low doses of EDCs influence certain human disorders is no longer conjecture, because epidemiological studies show that environmental exposures to EDCs are associated with human diseases and disabilities. We conclude that when nonmonotonic dose-response curves occur, the effects of low doses cannot be predicted by the effects observed at high doses. Thus, fundamental changes in chemical testing and safety determination are needed to protect human health.
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Affiliation(s)
- Laura N Vandenberg
- Tufts University, Center for Regenerative and Developmental Biology, Department of Biology, 200 Boston Avenue, Suite 4600, Medford, Massachusetts 02155, USA.
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30
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Hampson E, Sankar JS. Hand preference in humans is associated with testosterone levels and androgen receptor gene polymorphism. Neuropsychologia 2012; 50:2018-25. [PMID: 22579704 DOI: 10.1016/j.neuropsychologia.2012.04.027] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Revised: 03/23/2012] [Accepted: 04/27/2012] [Indexed: 11/19/2022]
Abstract
Exposure of the central nervous system to androgens during the early developmental period has been proposed to play a role in the establishment of hand preference in males. Existing data, however, are inconclusive. In the present investigation, handedness was assessed in a large sample of left-, mixed-, and right-handed men (N=180) using a standardized handedness inventory. Saliva sampling was used to assay levels of bioavailable testosterone and DNA genotyping was carried out to quantify AR-CAG repeat length, a genetic marker of the capacity of the androgen receptor to respond to testosterone. Strongly left-handed males were found to have lower levels of bioavailable testosterone than right-handed males, while males with mixed handedness exhibited a weaker androgen receptor, but no significant difference from right-handers in circulating testosterone levels. These findings support the view that testosterone could play a role in the development of hand preference in males. Furthermore, because the AR gene lies on the X chromosome, it provides a potential theoretical bridge to genetic theories of handedness that postulate the existence of an X-linked locus important in the establishment of hand preference.
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Affiliation(s)
- Elizabeth Hampson
- Department of Psychology, University of Western Ontario, London, ON, Canada N6A 5C2.
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31
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Lenz B, Müller CP, Stoessel C, Sperling W, Biermann T, Hillemacher T, Bleich S, Kornhuber J. Sex hormone activity in alcohol addiction: integrating organizational and activational effects. Prog Neurobiol 2011; 96:136-63. [PMID: 22115850 DOI: 10.1016/j.pneurobio.2011.11.001] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Revised: 11/03/2011] [Accepted: 11/08/2011] [Indexed: 01/06/2023]
Abstract
There are well-known sex differences in the epidemiology and etiopathology of alcohol dependence. Male gender is a crucial risk factor for the onset of alcohol addiction. A directly modifying role of testosterone in alcohol addiction-related behavior is well established. Sex hormones exert both permanent (organizational) and transient (activational) effects on the human brain. The sensitive period for these effects lasts throughout life. In this article, we present a novel early sex hormone activity model of alcohol addiction. We propose that early exposure to sex hormones triggers structural (organizational) neuroadaptations. These neuroadaptations affect cellular and behavioral responses to adult sex hormones, sensitize the brain's reward system to the reinforcing properties of alcohol and modulate alcohol addictive behavior later in life. This review outlines clinical findings related to the early sex hormone activity model of alcohol addiction (handedness, the second-to-fourth-finger length ratio, and the androgen receptor and aromatase) and includes clinical and preclinical literature regarding the activational effects of sex hormones in alcohol drinking behavior. Furthermore, we discuss the role of the hypothalamic-pituitary-adrenal and -gonadal axes and the opioid system in mediating the relationship between sex hormone activity and alcohol dependence. We conclude that a combination of exposure to sex hormones in utero and during early development contributes to the risk of alcohol addiction later in life. The early sex hormone activity model of alcohol addiction may prove to be a valuable tool in the development of preventive and therapeutic strategies.
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Affiliation(s)
- Bernd Lenz
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander-University of Erlangen-Nuremberg, Germany.
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32
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Tapp AL, Maybery MT, Whitehouse AJO. Evaluating the twin testosterone transfer hypothesis: a review of the empirical evidence. Horm Behav 2011; 60:713-22. [PMID: 21893061 DOI: 10.1016/j.yhbeh.2011.08.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2010] [Revised: 08/17/2011] [Accepted: 08/19/2011] [Indexed: 11/26/2022]
Abstract
In this paper we review the evidence that fetuses gestated with a male co-twin are masculinized in development, perhaps due to the influence of prenatal androgens: the so-called twin testosterone transfer (TTT) hypothesis. Evidence from studies of behavioral, perceptual, cognitive, morphological and physiological traits in same- and opposite-sex human twins is considered. Apart from two studies reporting increases in aspects of sensation-seeking for females with a male rather than a female co-twin, there is sparse evidence supporting the TTT hypothesis in behavioral studies. Outcomes from studies of perception (in particular otoacoustic emissions) and cognition (in particular vocabulary acquisition and visuo-spatial ability) provide more consistent evidence in support of masculinized performance in twins with a male co-twin compared to twins with a female co-twin. The outcomes favorable to the TTT hypothesis for otoacoustic emissions and visuo-spatial ability are restricted to females. Studies of physiology and morphology (e.g., brain volume, tooth size and 2D:4D ratio) also show some influence of co-twin sex, but again these effects are often restricted to female twins. Because females produce little endogenous testosterone, the effects of gestation with a male co-twin may be more pronounced in females than males. Thus, while uneven, the evidence for the TTT hypothesis is sufficient to warrant further investigation, ideally using large samples of same- and opposite-sex twins, along with control groups of same- and opposite-sex siblings when the characteristics assessed are potentially open to social influences.
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Affiliation(s)
- Aimee L Tapp
- Neurocognitive Development Unit, School of Psychology, University of Western Australia, Australia
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33
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Slutske WS, Bascom EN, Meier MH, Medland SE, Martin NG. Sensation seeking in females from opposite- versus same-sex twin pairs: hormone transfer or sibling imitation? Behav Genet 2010; 41:533-42. [PMID: 21140202 DOI: 10.1007/s10519-010-9416-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Accepted: 11/10/2010] [Indexed: 11/30/2022]
Abstract
The aims of this study were to replicate the results of a previous study (Resnick et al. 1993) and to extend them by examining the evidence for prenatal exposure to androgens versus sibling imitation as a potential cause of group differences in levels of sensation seeking. Participants were members of the Australian Twin Registry who had participated in a structured interview study and completed the Zuckerman Sensation-Seeking Scale. Three sets of group comparisons were conducted: (1) the sensation seeking scores of females from same-sex twin pairs (n = 1,947) were compared to females from opposite-sex twin pairs (n = 564), (2) females from same-sex twin pairs without a brother (n = 580) were compared to same-sex females with a close-in-age older brother (n = 300), and (3) same-sex females who had a close-in-age older brother (n = 300) were compared to females from opposite-sex twin pairs (n = 564). Females from opposite-sex twin pairs obtained significantly higher scores than females from same-sex twin pairs on the experience-seeking (d = 0.12) and thrill and adventure seeking (d = 0.10) subscales, but not the boredom susceptibility (d = -0.01) or disinhibition (d < 0.01) subscales of the Sensation-Seeking Scale. The modest effects obtained could not be explained by the psychosocial effect of having a close-in-age brother. Considering these effects alongside the overall sex differences in the Sensation-Seeking Scales of experience-seeking (d = 0.12 vs. d = 0.18) and thrill and adventure-seeking (d = 0.10 vs. d = 0.83) suggests that prenatal androgens may actually play a large role in the sex difference in the personality trait of experience seeking, and a smaller role in thrill and adventure-seeking; there was no evidence from this study that prenatal androgens are important for explaining sex differences in the traits of boredom susceptibility or disinhibition.
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Affiliation(s)
- Wendy S Slutske
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA.
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