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Hopper JL, Li S, MacInnis RJ, Dowty JG, Nguyen TL, Bui M, Dite GS, Esser VFC, Ye Z, Makalic E, Schmidt DF, Goudey B, Alpen K, Kapuscinski M, Win AK, Dugué PA, Milne RL, Jayasekara H, Brooks JD, Malta S, Calais-Ferreira L, Campbell AC, Young JT, Nguyen-Dumont T, Sung J, Giles GG, Buchanan D, Winship I, Terry MB, Southey MC, Jenkins MA. Breast and bowel cancers diagnosed in people 'too young to have cancer': A blueprint for research using family and twin studies. Genet Epidemiol 2024. [PMID: 38504141 DOI: 10.1002/gepi.22555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 01/29/2024] [Accepted: 02/23/2024] [Indexed: 03/21/2024]
Abstract
Young breast and bowel cancers (e.g., those diagnosed before age 40 or 50 years) have far greater morbidity and mortality in terms of years of life lost, and are increasing in incidence, but have been less studied. For breast and bowel cancers, the familial relative risks, and therefore the familial variances in age-specific log(incidence), are much greater at younger ages, but little of these familial variances has been explained. Studies of families and twins can address questions not easily answered by studies of unrelated individuals alone. We describe existing and emerging family and twin data that can provide special opportunities for discovery. We present designs and statistical analyses, including novel ideas such as the VALID (Variance in Age-specific Log Incidence Decomposition) model for causes of variation in risk, the DEPTH (DEPendency of association on the number of Top Hits) and other approaches to analyse genome-wide association study data, and the within-pair, ICE FALCON (Inference about Causation from Examining FAmiliaL CONfounding) and ICE CRISTAL (Inference about Causation from Examining Changes in Regression coefficients and Innovative STatistical AnaLysis) approaches to causation and familial confounding. Example applications to breast and colorectal cancer are presented. Motivated by the availability of the resources of the Breast and Colon Cancer Family Registries, we also present some ideas for future studies that could be applied to, and compared with, cancers diagnosed at older ages and address the challenges posed by young breast and bowel cancers.
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Affiliation(s)
- John L Hopper
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Shuai Li
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - Robert J MacInnis
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia
| | - James G Dowty
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Tuong L Nguyen
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Minh Bui
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Gillian S Dite
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Genetic Technologies Ltd., Fitzroy, Victoria, Australia
| | - Vivienne F C Esser
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Zhoufeng Ye
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Enes Makalic
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Daniel F Schmidt
- Department of Data Science and AI, Faculty of Information Technology, Monash University, Melbourne, Victoria, Australia
| | - Benjamin Goudey
- ARC Training Centre in Cognitive Computing for Medical Technologies, University of Melbourne, Carlton, Victoria, Australia
- The Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Karen Alpen
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Miroslaw Kapuscinski
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Aung Ko Win
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- University of Melbourne Centre for Cancer Research, Victorian Comprehensive Cancer Centre, Melbourne, Victoria, Australia
- Genetic Medicine, Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Pierre-Antoine Dugué
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia
| | - Roger L Milne
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia
| | - Harindra Jayasekara
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia
| | - Jennifer D Brooks
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | - Sue Malta
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Lucas Calais-Ferreira
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
| | - Alexander C Campbell
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Jesse T Young
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
- Institute for Mental Health Policy Research, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Centre for Adolescent Health, Murdoch Children's Research Institute, Parkville, Victoria, Australia
- School of Population and Global Health, The University of Western Australia, Perth, Western Australia, Australia
- Justice Health Group, Curtin School of Population Health, Curtin University, Perth, Western Australia, Australia
| | - Tu Nguyen-Dumont
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - Joohon Sung
- Department of Public Health Sciences, Division of Genome and Health Big Data, Graduate School of Public Health, Seoul National University, Seoul, South Korea
- Genome Medicine Institute, Seoul National University, Seoul, South Korea
- Institute of Health and Environment, Seoul National University, Seoul, South Korea
| | - Graham G Giles
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia
| | - Daniel Buchanan
- Department of Clinical Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Ingrid Winship
- Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, Victoria, Australia
| | - Mary Beth Terry
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Melissa C Southey
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia
- Department of Clinical Pathology, The University of Melbourne, Parkville, Victoria, Australia
| | - Mark A Jenkins
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Carlton, Victoria, Australia
- University of Melbourne Centre for Cancer Research, Victorian Comprehensive Cancer Centre, Melbourne, Victoria, Australia
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Jang JY, Beam CR, Karlsson IK, Pedersen NL, Gatz M. Dementia and mortality in older adults: A twin study. Alzheimers Dement 2024; 20:1682-1692. [PMID: 38078564 PMCID: PMC10947969 DOI: 10.1002/alz.13553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 09/28/2023] [Accepted: 10/22/2023] [Indexed: 12/17/2023]
Abstract
INTRODUCTION Dementia predicts increased mortality. We used case-control and co-twin control models to investigate genetic and shared environmental influences on this association. METHODS Case-control design, including 987 twins with dementia and 2938 age- and sex-matched controls in the Swedish Twin Registry. Co-twin control design, including 90 monozygotic (MZ) and 288 dizygotic (DZ) twin pairs discordant for dementia. To test for genetic and environmental confounding, differences were examined in mortality risk between twins with dementia and their matched or co-twin controls. RESULTS Twins with dementia showed greater mortality risk than age- and sex-matched controls (HR = 2.02 [1.86, 2.18]). Mortality risk is significantly elevated but attenuated substantially in discordant twin pairs, for example, comparing MZ twins with dementia to their co-twin controls (HR = 1.48 [1.08, 2.04]). DISCUSSION Findings suggest that genetic factors partially confound the association between dementia and mortality and provide an alternative hypothesis to increased mortality due to dementia itself. Highlights We studied dementia and mortality in twin pairs discordant for dementia. People without dementia outlived people with dementia. Identical twins with dementia and their co-twin controls had similar survival time. Findings suggest genotype may explain the link between dementia and mortality.
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Affiliation(s)
- Jung Yun Jang
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, California, USA
| | - Christopher R Beam
- Department of Psychology, University of Southern California, Los Angeles, California, USA
- Davis School of Gerontology, University of Southern California, Los Angeles, California, USA
| | - Ida K Karlsson
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Nancy L Pedersen
- Department of Psychology, University of Southern California, Los Angeles, California, USA
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Margaret Gatz
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- Center for Economic and Social Research, University of Southern California, Los Angeles, California, USA
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Nilsson A, Kuja‐Halkola R, Lichtenstein P, Larsson H, Lundström S, Fatouros‐Bergman H, Jayaram‐Lindström N, Molero Y. The genetics of gaming: A longitudinal twin study. JCPP Adv 2023; 3:e12179. [PMID: 38054048 PMCID: PMC10694538 DOI: 10.1002/jcv2.12179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 04/21/2023] [Indexed: 12/07/2023] Open
Abstract
Background Gaming is a popular past-time activity among children and adolescents, but it there is also a possible link to negative consequences such as psychological distress and lowered academic achievement. However, there are fundamental knowledge gaps remaining regarding central characteristics of gaming such as heritability, stability over time, and sex differences. We examined the genetic and environmental contribution to gaming behavior, including sex differences, continuity and change, in a longitudinal cohort of twins. Methods This is the first longitudinal twin study on gaming, involving 32,006 twins in Sweden. Parents were asked about the twins' gaming at ages 9, 15 and 18. We used univariate and multivariate twin analyses to estimate the relative contribution of genetic and environmental influences at each time-point as well as across time. Sex-differences were also explored. Results The results showed large sex differences, where genetics explained more of the variance for boys (31.3%-62.5% depending on age) than for girls (19.4%-23.4%). Genetic factors explained an increasing amount of the variance for boys (31.3% at age 9, 62.5% at age 15 and 53.9% at age 18). Shared environmental factors explained a larger proportion of the variance among girls, which remained relatively stable over time (70.5% at age 9, 61.8% at age 15 and 60.5% at age 18). The results also indicated that most of the variance came from genetic and environmental sources specific to each age. Conclusions Compared to many other behavioral phenotypes, such as gambling, gaming was relatively unstable with a large degree of genetic innovation. There were large sex differences in the contribution of genetic and environmental factors. This suggests that excessive gaming could be the result of age- and sex-specific genetic and environmental factors, and should be taken into account when mapping gaming behaviors, since these behaviors might be under continual etiological transformation.
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Affiliation(s)
- Anders Nilsson
- Department of Clinical NeuroscienceCentre for Psychiatry ResearchKarolinska InstitutetStockholmSweden
- Stockholm Health Care ServicesStockholmSweden
| | - Ralf Kuja‐Halkola
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Paul Lichtenstein
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Henrik Larsson
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
| | - Sebastian Lundström
- Gillberg Neuropsychiatry CentreInstitute of Neuroscience and PhysiologyUniversity of GothenburgGothenburgSweden
- Center for Ethics, Law and Mental Health (CELAM)Institute of Neuroscience and PhysiologyUniversity of GothenburgGothenburgSweden
| | - Helena Fatouros‐Bergman
- Department of Clinical NeuroscienceCentre for Psychiatry ResearchKarolinska InstitutetStockholmSweden
- Stockholm Health Care ServicesStockholmSweden
| | - Nitya Jayaram‐Lindström
- Department of Clinical NeuroscienceCentre for Psychiatry ResearchKarolinska InstitutetStockholmSweden
- Stockholm Health Care ServicesStockholmSweden
| | - Yasmina Molero
- Department of Clinical NeuroscienceCentre for Psychiatry ResearchKarolinska InstitutetStockholmSweden
- Stockholm Health Care ServicesStockholmSweden
- Department of Medical Epidemiology and BiostatisticsKarolinska InstitutetStockholmSweden
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Kamzolas O, Papazoglou AS, Gemousakakis E, Moysidis DV, Kyriakoulis KG, Brilakis ES, Milkas A. Concomitant Coronary Artery Disease in Identical Twins: Case Report and Systematic Literature Review. J Clin Med 2023; 12:5742. [PMID: 37685809 PMCID: PMC10489011 DOI: 10.3390/jcm12175742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 08/29/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023] Open
Abstract
Coronary artery disease (CAD) is multifactorial and strongly affected by genetic, epigenetic and environmental factors. Several studies have reported development of concomitant CAD in identical twins. We report a case in which a pair of Caucasian male monozygotic twins presented almost concomitantly with acute coronary syndrome (ACS) and had concordant coronary anatomy and identical site of occlusion. We performed a systematic literature review of PubMed, Web Of Science and Scopus databases from inception until 28 February 2023 of case reports/case series reporting the concomitant development of CAD in monozygotic twins. We found 25 eligible case reports with a total of 31 monozygotic twin pairs (including the case from our center) suffering from CAD and presenting (most of them simultaneously) with ACS (mean age of presentation: 45 ± 12 years, males: 81%). Coronary angiograms demonstrated lesion and anatomy concordance in 77% and 79% of the twin pairs, respectively. Screening for disease-related genetic mutations was performed in six twin pairs leading to the identification of five CAD-related genetic polymorphisms. This is the first systematic literature review of studies reporting identical twin pairs suffering from CAD. In summary, there is high concordance of coronary anatomy and clinical presentation between monozygotic twins. Future monozygotic twin studies-unbiased by age effects-can provide insights into CAD heritability being able to disentangle the traditional dyad of genetic and environmental factors and investigate the within-pair epigenetic drift.
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Affiliation(s)
| | | | | | | | | | - Emmanouil S Brilakis
- Center for Coronary Artery Disease, Minneapolis Heart Institute and Minneapolis Heart Institute Foundation, Abbott Northwestern, Minneapolis, MN 55407, USA
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Stolarski M, Zawadzki B, Matthews G, Pruszczak D, Wojciechowski J. Behavioral genetics of temporal framing: Heritability of time perspective and its common genetic bases with major personality traits. J Pers 2023. [PMID: 37551866 DOI: 10.1111/jopy.12870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 05/26/2023] [Accepted: 07/19/2023] [Indexed: 08/09/2023]
Abstract
OBJECTIVE The present study aimed to provide a seminal behavioral genetic analysis of time perspectives (TPs). Moreover, we intended to investigate the magnitude of genetic vs. environmental components of the well-established assocations between TPs and personality features. BACKGROUND Individual differences in temporal framing processes, referred to as TPs, are vital psychological and behavioral outcomes. Although proponents of TP theory emphasize mainly environmental origins of the tendencies to adopt certain TPs, research provides evidence for marked associations between the temporal dimensions and major personality traits that are known to be heritable. Hence, it was essential to empirically verify these claims. METHOD The article reports an analysis of genetic and environmental components of variance in TPs based on a study adopting a twin design, conducted on a sample of 393 pairs of twins (135 monozygotic and 258 dizygotic). RESULTS Multivariate Cholesky decomposition supported an EA model assuming impacts of both unshared environmental factors (E) and additive genetic factors (A) across all TP dimensions, suggesting that the effects of shared environment on TPs are plausibly negligible. Heritability indices of TPs ranged between 0.51 for Present-Fatalistic and 0.62 for Present-Hedonistic, suggesting that the majority of the variance in TPs stems from genetic influences. Substantial genetic correlations were found between TPs and the Big Five personality traits. CONCLUSIONS The findings provide further evidence for conceptualizing TPs as biologically based personality traits and challenge the claims that TP is mainly a product of culture, education, and personal experiences.
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Affiliation(s)
| | | | - Gerald Matthews
- Department of Psychology, George Mason University, Fairfax, Virginia, USA
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Larsen SA, Asbury K, Coventry WL, Hart SA, Little CW, Petrill SA. Measuring CHAOS? Evaluating the short-form Confusion, Hubbub And Order Scale. Collabra Psychol 2023; 9:77837. [PMID: 38528944 PMCID: PMC10961925 DOI: 10.1525/collabra.77837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
The Confusion, Hubbub and Order Scale (CHAOS) - short form - is a survey tool intended to capture information about home environments. It is widely used in studies of child and adolescent development and psychopathology, particularly twin studies. The original long form of the scale comprised 15 items and was validated in a sample of infants in the 1980s. The short form of the scale was developed in the late 1990s and contains six items, including four from the original scale, and two new items. This short form has not been validated and is the focus of this study. We use five samples drawn from twin studies in Australia, the UK, and the USA, and examine measurement invariance of the CHAOS short-form. We first compare alternate confirmatory factor models for each group; we next test between-group configural, metric and scalar invariance; finally, we examine predictive validity of the scale under different conditions. We find evidence that a two-factor configuration of the six items is more appropriate than the commonly used one-factor model. Second, we find measurement non-invariance across groups at the metric invariance step, with items performing differently depending on the sample. We also find inconsistent results in tests of predictive validity using family-level socioeconomic status and academic achievement as criterion variables. The results caution the continued use of the short-form CHAOS in its current form and recommend future revisions and development of the scale for use in developmental research.
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Affiliation(s)
| | | | | | - Sara A. Hart
- Department of Psychology, Florida State University, USA
- Florida Center for Reading Research, Florida State University, USA
| | - Callie W. Little
- Florida Center for Reading Research, Florida State University, USA
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Vaajala M, Liukkonen R, Kuitunen I, Ponkilainen V, Kekki M, Mattila VM. Obesity increases the odds of multiple pregnancies: A nationwide register-based cohort study in Finland. Int J Gynaecol Obstet 2023. [PMID: 36916851 DOI: 10.1002/ijgo.14748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 03/03/2023] [Indexed: 03/16/2023]
Abstract
OBJECTIVE To investigate the effects of increased pre-pregnancy body mass index (BMI, calculated as weight in kilograms divided by the square of height in meters) on the risk of having spontaneous multiple pregnancies using a nationwide register-based study sample. METHODS Data from the National Medical Birth Register (MBR) (2004-2018) were used to evaluate the effects of a higher pre-pregnancy BMI on the risk of multiple pregnancies. Lower and higher pre-pregnancy BMI classes, using the WHO classification, were compared with a normal weight class. A logistic regression model was used to assess the primary outcomes. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) between the groups were compared. The model was adjusted by maternal age, maternal height, and maternal smoking status. RESULTS The odds of multiple pregnancies were higher among women in the overweight group (aOR 1.07, 95% CI 1.02-1.12), obesity class I group (aOR 1.11, 95% CI 1.04-1.18), and obesity class II group (aOR 1.15, 95% CI 1.03-1.28) compared with women in the non-overweight BMI class. Women in the underweight group had lower odds for multiple pregnancies (aOR 0.82, 95% CI 0.73-0.93). CONCLUSION The odds of multiple pregnancies slightly increase with pre-pregnancy obesity, and this should be acknowledged as a minor risk factor for multiple pregnancies.
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Affiliation(s)
- Matias Vaajala
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland
| | - Rasmus Liukkonen
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland
| | - Ilari Kuitunen
- Department of Pediatrics, Mikkeli Central Hospital, Mikkeli, Finland.,Institute of Clinical Medicine and Department of Pediatrics, University of Eastern Finland, Kuopio, Finland
| | - Ville Ponkilainen
- Department of Surgery, Central Finland Central Hospital Nova, Jyväskylä, Finland
| | - Maiju Kekki
- Department of Obstetrics and Gynecology, Tampere University Hospital, Tampere, Finland.,Center for Child, Adolescent and Maternal Health Research, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Ville M Mattila
- Faculty of Medicine and Life Sciences, University of Tampere, Tampere, Finland.,Department of Orthopedics and Traumatology, Tampere University Hospital, Tampere, Finland
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Happle R, Wetzke M. Superimposed mosaicism in cutaneous sarcoidosis: A hypothesis. Am J Med Genet A 2023; 191:899-901. [PMID: 36448706 DOI: 10.1002/ajmg.a.63058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 09/26/2022] [Accepted: 11/08/2022] [Indexed: 12/05/2022]
Abstract
Sarcoidosis is a chronic granulomatous disorder affecting the lungs, skin, and many other organs. Twin studies suggest that genetic factors account, to a large degree, for the etiology of the disorder. Hence, theoretically, we could postulate that the phenomenon of superimposed mosaicism in the form of a pronounced segmental involvement, overlaying the disseminated non-segmental lesions, should also occur in sarcoidosis. Indeed, one case suggesting superimposed mosaicism in cutaneous sarcoidosis was found in the literature and is reassessed here.
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Affiliation(s)
- Rudolf Happle
- Department of Dermatology, Medical Center-University of Freiburg, Freiburg, Germany
| | - Martin Wetzke
- Department of Paediatric Pneumology and Neonatology, Hannover Medical School, Hannover, Germany
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Abstract
Twin and family studies show a strong contribution of genetic factors to physical activity (PA) assessed by either self-report or accelerometers. PA heritability is around 43% across the lifespan. Genome-wide association studies have implied biological pathways related to exercise ability and enjoyment. A polygenic score based on genetic variants influencing PA could help improve the success of intervention programs.
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Plassman BL, Chanti-Ketterl M, Pieper CF, Yaffe K. Traumatic brain injury and dementia risk in male veteran older twins-Controlling for genetic and early life non-genetic factors. Alzheimers Dement 2022; 18:2234-2242. [PMID: 35102695 PMCID: PMC9339591 DOI: 10.1002/alz.12571] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 12/05/2021] [Accepted: 12/08/2021] [Indexed: 01/31/2023]
Abstract
INTRODUCTION This study leveraged the twin study design, which controls for shared genetic and early life exposures, to investigate the association between traumatic brain injury (TBI) and dementia. METHODS Members of the National Academy of Sciences-National Research Council's Twins Registry of World War II male veterans were assigned a cognitive outcome based on a multi-step assessment protocol. History of TBI was obtained via interviews. RESULTS Among 8302 individuals, risk of non-Alzheimer's disease (non-AD) dementia was higher in those with TBI (hazard ratio [HR] = 2.00, 95% confidence interval [CI], 0.97-4.12), than for AD (HR = 1.23, 95% CI, 0.76-2.00). To add more control of genetic and shared environmental factors, we analyzed 100 twin pairs discordant for both TBI and dementia onset, and found TBI-associated risk for non-AD dementia increased further (McNemar odds ratio = 2.70; 95% CI, 1.27-6.25). DISCUSSION These findings suggest that non-AD mechanisms may underlie the association between TBI and dementia, potentially providing insight into inconsistent results from prior studies.
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Affiliation(s)
- Brenda L. Plassman
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC
- Department of Neurology, Duke University Medical Center, Durham, NC
- Center for Aging and Human Development, Duke University Medical Center, Durham, NC
| | - Marianne Chanti-Ketterl
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC
- Center for Aging and Human Development, Duke University Medical Center, Durham, NC
| | - Carl F. Pieper
- Center for Aging and Human Development, Duke University Medical Center, Durham, NC
- Dept. Biostatistics and Bioinformatics. Duke University Medical Center, Durham, NC
| | - Kristine Yaffe
- Departments of Psychiatry and Behavioral Sciences, Neurology and Epidemiology and Biostatistics, University of California, San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, CA
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Kendler KS, Klee A. The Beginnings of Scientific Psychiatric Twin Research: Luxenburger's 1928 "Preliminary Report on the Psychiatric Examination of a Series of Twins". Schizophr Bull 2022; 48:S37-S44. [PMID: 36260541 PMCID: PMC9581073 DOI: 10.1093/schbul/sbac110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
While reports of twin pairs concordant for insanity began to appear in the 19th century, the first modern psychiatric twin study that fulfilled Galton's 1875 promise of the value of the twin method was published by the German Psychiatrist and Geneticist Hans Luxenburger in 1928. Luxenburger introduced four major methodological advances: the use of representative sampling, proband-wise concordance, rigorous zygosity diagnoses, and age correction. He used a narrow Kraepelinian diagnostic approach diagnosis and ascertained twins hospitalized, on a specific day, in all large Bavarian asylums. We include a brief biography of Luxenburger, summarize the findings of his paper and provide a full English translation in the appendix. Luxenburger presents evidence that the frequency of twinning in those with severe mental illness were as expected and reports proband-wise concordance for probable and definite dementia praecox (MZ-76%, DZ-0%) and manic-depressive insanity (MZ-75%, DZ-0%). He also examined eccentricity and hyperthymic or hypothymic personality in the dementia praecox and manic-depressive pairs, respectively. Luxenburger's substantial contributions to the history of psychiatric genetics should be considered in the context of his intimate but ambivalent relationship with the racial-hygiene policy of the German National Socialists.
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Affiliation(s)
- Kenneth S Kendler
- Department of Psychiatry, Virginia Institute of Psychiatric and Behavioral Genetics, Medical College of Virginia/Virginia Commonwealth University, Richmond, VA, USA
| | - Astrid Klee
- Department of Germanic Languages and Literatures, University of Toronto, Canada
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12
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Ingelman-Sundberg M. The missing heritability in pharmacogenomics: role of NFIB and other factors. Pharmacogenomics 2022; 23:453-455. [PMID: 35546341 DOI: 10.2217/pgs-2022-0054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Magnus Ingelman-Sundberg
- Department of Physiology & Pharmacology, Section of Pharmacogenetics, Biomedicum 5B, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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13
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Erbeli F, Rice M, Paracchini S. Insights into Dyslexia Genetics Research from the Last Two Decades. Brain Sci 2021; 12:27. [PMID: 35053771 PMCID: PMC8773624 DOI: 10.3390/brainsci12010027] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/21/2021] [Accepted: 12/23/2021] [Indexed: 12/14/2022] Open
Abstract
Dyslexia, a specific reading disability, is a common (up to 10% of children) and highly heritable (~70%) neurodevelopmental disorder. Behavioral and molecular genetic approaches are aimed towards dissecting its significant genetic component. In the proposed review, we will summarize advances in twin and molecular genetic research from the past 20 years. First, we will briefly outline the clinical and educational presentation and epidemiology of dyslexia. Next, we will summarize results from twin studies, followed by molecular genetic research (e.g., genome-wide association studies (GWASs)). In particular, we will highlight converging key insights from genetic research. (1) Dyslexia is a highly polygenic neurodevelopmental disorder with a complex genetic architecture. (2) Dyslexia categories share a large proportion of genetics with continuously distributed measures of reading skills, with shared genetic risks also seen across development. (3) Dyslexia genetic risks are shared with those implicated in many other neurodevelopmental disorders (e.g., developmental language disorder and dyscalculia). Finally, we will discuss the implications and future directions. As the diversity of genetic studies continues to increase through international collaborate efforts, we will highlight the challenges in advances of genetics discoveries in this field.
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Affiliation(s)
- Florina Erbeli
- Department of Educational Psychology, Texas A&M University, College Station, TX 77843, USA;
| | - Marianne Rice
- Department of Educational Psychology, Texas A&M University, College Station, TX 77843, USA;
| | - Silvia Paracchini
- School of Medicine, University of St Andrews, St Andrews KY16 9AJ, UK;
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14
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Belfry KD, Kolla NJ. Cold-Blooded and on Purpose: A Review of the Biology of Proactive Aggression. Brain Sci 2021; 11:1412. [PMID: 34827411 PMCID: PMC8615983 DOI: 10.3390/brainsci11111412] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/15/2021] [Accepted: 10/20/2021] [Indexed: 12/29/2022] Open
Abstract
Proactive aggression (PA) is a planned and unprovoked form of aggression that is most often enacted for personal gain or in anticipation of a reward. Frequently described as "cold-blooded" or goal oriented, PA is thought to be associated with low autonomic arousal. With this view in mind, we performed a scoping review of the biological correlates of PA and identified 74 relevant articles. Physiological findings indicated a robust association between PA and reduced resting heart rate, and to a lesser extent a relationship between PA and decreased heart rate and skin conductance reactivity, perhaps indicating dampened sympathetic function. The twin literature identified PA as a heritable trait, but little evidence implicates specific genes in the pathogenesis of PA. Neuroimaging studies of PA pinpoint impaired amygdala function in the assessment and conditioning of aversive stimuli, which may influence the establishment of behavioral patterns. Nodes of the default mode network were identified as possible neural correlates of PA, suggesting that altered function of this network may be involved in the genesis of PA. Given the overlap of PA with reactive aggression and the overall behavioral complexity of PA, it is clear that multiple endophenotypes of PA exist. This comprehensive review surveys the most salient neurobiologically informed research on PA.
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Affiliation(s)
- Kimberly D. Belfry
- Waypoint Research Institute, Waypoint Centre for Mental Health Care, Penetanguishene, ON L9M 1G3, Canada;
| | - Nathan J. Kolla
- Waypoint Research Institute, Waypoint Centre for Mental Health Care, Penetanguishene, ON L9M 1G3, Canada;
- Department of Psychiatry, University of Toronto, Toronto, ON M5S 1A1, Canada
- Centre for Addiction and Mental Health (CAMH), Toronto, ON M5T 1R8, Canada
- Violence Prevention Neurobiological Research Unit, CAMH, Toronto, ON M5T 1R8, Canada
- Waypoint/University of Toronto Research Chair in Forensic Mental Health Science, Penetanguishene, ON L9M 1G3, Canada
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15
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Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a common and highly heritable neurodevelopmental disorder (NDD). In this narrative review, we summarize recent advances in quantitative and molecular genetic research from the past 5-10 years. Combined with large-scale international collaboration, these advances have resulted in fast-paced progress in understanding the etiology of ADHD and how genetic risk factors map on to clinical heterogeneity. Studies are converging on a number of key insights. First, ADHD is a highly polygenic NDD with a complex genetic architecture encompassing risk variants across the spectrum of allelic frequencies, which are implicated in neurobiological processes. Second, genetic studies strongly suggest that ADHD diagnosis shares a large proportion of genetic risks with continuously distributed traits of ADHD in the population, with shared genetic risks also seen across development and sex. Third, ADHD genetic risks are shared with those implicated in many other neurodevelopmental, psychiatric and somatic phenotypes. As sample sizes and the diversity of genetic studies continue to increase through international collaborative efforts, we anticipate further success with gene discovery, characterization of how the ADHD phenotype relates to other human traits and growing potential to use genomic risk factors for understanding clinical trajectories and for precision medicine approaches.
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Affiliation(s)
- Isabell Brikell
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- National Centre for Register-based Research, Department of Economics and Business Economics, Aarhus University, Aarhus, Denmark
| | - Christie Burton
- Neurosciences and Mental Health, Hospital for Sick Children, Toronto, Canada
| | - Nina Roth Mota
- Department of Human Genetics, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
| | - Joanna Martin
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, UK
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16
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Matveeva N, Titov B, Bazyleva E, Pevzner A, Favorova O. Towards Understanding the Genetic Nature of Vasovagal Syncope. Int J Mol Sci 2021; 22:10316. [PMID: 34638656 PMCID: PMC8508958 DOI: 10.3390/ijms221910316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/21/2021] [Accepted: 09/23/2021] [Indexed: 11/17/2022] Open
Abstract
Syncope, defined as a transient loss of consciousness caused by transient global cerebral hypoperfusion, affects 30-40% of humans during their lifetime. Vasovagal syncope (VVS) is the most common cause of syncope, the etiology of which is still unclear. This review summarizes data on the genetics of VVS, describing the inheritance pattern of the disorder, candidate gene association studies and genome-wide studies. According to this evidence, VVS is a complex disorder, which can be caused by the interplay between genetic factors, whose contribution varies from monogenic Mendelian inheritance to polygenic inherited predisposition, and external factors affecting the monogenic (resulting in incomplete penetrance) and polygenic syncope types.
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Affiliation(s)
- Natalia Matveeva
- National Medical Research Center for Cardiology, 121552 Moscow, Russia; (N.M.); (B.T.); (E.B.); (A.P.)
- Department of Molecular Biology and Medical Biotechnology, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Boris Titov
- National Medical Research Center for Cardiology, 121552 Moscow, Russia; (N.M.); (B.T.); (E.B.); (A.P.)
- Department of Molecular Biology and Medical Biotechnology, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Elizabeth Bazyleva
- National Medical Research Center for Cardiology, 121552 Moscow, Russia; (N.M.); (B.T.); (E.B.); (A.P.)
| | - Alexander Pevzner
- National Medical Research Center for Cardiology, 121552 Moscow, Russia; (N.M.); (B.T.); (E.B.); (A.P.)
| | - Olga Favorova
- National Medical Research Center for Cardiology, 121552 Moscow, Russia; (N.M.); (B.T.); (E.B.); (A.P.)
- Department of Molecular Biology and Medical Biotechnology, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
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17
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Abstract
OBJECTIVE Prior research on the causality and directionality between disease and functional limitations is ambiguous. The current study used longitudinal monozygotic twin data to test both directions linking disease burden and functional limitations in middle-aged and older adults, controlling for genetic and familial factors. We also examined potential moderation by psychological well-being. METHODS The twin subsample from the first two waves of the longitudinal Midlife in the United States (MIDUS) study was used (wave 1, 1995-1996; wave 2, 2004-2006). Only monozygotic twins (n = 713) were included in analyses. In separate multilevel models, we examined disease burden at MIDUS 2 predicted by functional limitations at MIDUS 1 and MIDUS 2 functional limitations predicted by disease burden at MIDUS 1. RESULTS Disease burden and functional limitations at MIDUS 2 varied substantially within families. There was no within-family association of earlier functional limitations with change in later disease burden (b = 0.40, p = .39), but there was a within-family association such that the twin with higher baseline disease burden had a greater increase in functional limitations than his/her co-twin (b = 0.06, p = .02). Well-being was not a moderator in either model. CONCLUSIONS We found support for a potentially causal association between earlier disease burden and later increases in functional limitations, consistent with the Disablement Process Model. Sensitivity analyses confirm the detected within-family effect. Possible mechanisms linking disease burden and functional limitations are discussed as potential targets for future research.
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Affiliation(s)
- Elizabeth Teas
- Department of Human Development and Family Studies, Purdue University, West Lafayette, IN, USA
- Center for Aging and the Life Course, Purdue University, West Lafayette, IN, USA
| | - Olivia Robertson
- Department of Human Development and Family Studies, Purdue University, West Lafayette, IN, USA
| | - Kristine Marceau
- Department of Human Development and Family Studies, Purdue University, West Lafayette, IN, USA
| | - Elliot Friedman
- Department of Human Development and Family Studies, Purdue University, West Lafayette, IN, USA
- Center for Aging and the Life Course, Purdue University, West Lafayette, IN, USA
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18
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Skov J, Calissendorff J, Eriksson D, Magnusson P, Kämpe O, Bensing S, Kuja-Halkola R. Limited Genetic Overlap Between Overt Hashimoto's Thyroiditis and Graves' Disease in Twins: A Population-based Study. J Clin Endocrinol Metab 2021; 106:1101-1110. [PMID: 33382429 PMCID: PMC7993582 DOI: 10.1210/clinem/dgaa956] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Indexed: 11/19/2022]
Abstract
CONTEXT Hashimoto's thyroiditis (HT) and Graves' disease (GD) are known to coaggregate in families, but the magnitude and nature of a shared etiology is unknown. OBJECTIVES To estimate the shared genetic influence on overt HT and GD and to examine if the heritability differs between men and women. DESIGN, SETTING, AND PATIENTS We used national health registries to identify cases of HT and GD in a cohort of 110 814 Swedish twins. By comparing intra-class and cross-twin cross-trait correlations in dizygotic and monozygotic twins, we calculated heritability and the proportions thereof shared between the diseases. Univariate estimates of heritability were calculated by sex. RESULTS The heritability for HT and GD was 65% (95% CI, 61-70) and 63% (95% CI, 55-72), respectively. The genetic correlation was 0.35 (95% CI, 0.20-0.50) and shared genetic effects accounted for 8% of the variance for both HT and GD. Univariate heritability was significantly higher in men than in women for HT (90% vs 60%, P < 0.001) but not for GD (79% vs 63%, P = 0.085). CONCLUSIONS From a genetic perspective, HT and GD appear to be only modestly related diseases. Hence, the term "autoimmune thyroid disease," used to cluster these disorders, may have limited validity in a genetic context. Moreover, the mechanisms contributing to HT are partly different for the sexes, with genetic components more important in men.
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Affiliation(s)
- Jakob Skov
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Medicine, Karlstad Central Hospital, Karlstad, Sweden
| | - Jan Calissendorff
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Endocrinology, Inflammation and Infection Theme, Karolinska University Hospital, Stockholm, Sweden
| | - Daniel Eriksson
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
- Department of Clinical Genetics, Uppsala University Hospital, Uppsala, Sweden
- Department of Medicine (Solna), Karolinska Institutet, Stockholm, Sweden
| | - Patrik Magnusson
- Department of Medical Epidemiology and Biostatistics Karolinska Institutet, Stockholm, Sweden
| | - Olle Kämpe
- Department of Endocrinology, Inflammation and Infection Theme, Karolinska University Hospital, Stockholm, Sweden
- Department of Medicine (Solna), Karolinska Institutet, Stockholm, Sweden
- K.G. Jebsen Center for Autoimmune Diseases, University of Bergen, Norway
| | - Sophie Bensing
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Endocrinology, Inflammation and Infection Theme, Karolinska University Hospital, Stockholm, Sweden
| | - Ralf Kuja-Halkola
- Department of Medical Epidemiology and Biostatistics Karolinska Institutet, Stockholm, Sweden
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19
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Abstract
Behavior genetics studies how genetic differences among people contribute to differences in their psychology and behavior. Here, I describe how the conclusions and methods of behavior genetics have evolved in the postgenomic era in which the human genome can be directly measured. First, I revisit the first law of behavioral genetics stating that everything is heritable, and I describe results from large-scale meta-analyses of twin data and new methods for estimating heritability using measured DNA. Second, I describe new methods in statistical genetics, including genome-wide association studies and polygenic score analyses. Third, I describe the next generation of work on gene × environment interaction, with a particular focus on how genetic influences vary across sociopolitical contexts and exogenous environments. Genomic technology has ushered in a golden age of new tools to address enduring questions about how genes and environments combine to create unique human lives.
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Affiliation(s)
- K Paige Harden
- Department of Psychology, University of Texas at Austin, Austin, Texas 78712, USA;
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20
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Berentsen GD, Azzolini F, Skaug HJ, Lie RT, Gjessing HK. Heritability curves: A local measure of heritability in family models. Stat Med 2020; 40:1357-1382. [PMID: 33336424 DOI: 10.1002/sim.8845] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 10/14/2020] [Accepted: 11/21/2020] [Indexed: 11/07/2022]
Abstract
Classical heritability models for family data split the phenotype variance into genetic and environmental components. For instance, the ACE model in twin studies assumes the phenotype variance decomposes as a2 + c2 + e2 , representing (additive) genetic effects, common (shared) environment, and residual environment, respectively. However, for some phenotypes it is biologically plausible that the genetic and environmental components may vary over the range of the phenotype. For instance, very large or small values of the phenotype may be caused by "sporadic" environmental factors, whereas the mid-range phenotype variation may be more under the control of common genetic factors. This article introduces a "local" measure of heritability, where the genetic and environmental components are allowed to depend on the value of the phenotype itself. Our starting point is a general formula for local correlation between two random variables. For estimation purposes, we use a multivariate Gaussian mixture, which is able to capture nonlinear dependence and respects certain distributional constraints. We derive an analytical expression for the associated correlation curve, and show how to decompose the correlation curve into genetic and environmental parts, for instance, a2 (y) + c2 (y) + e2 (y) for the ACE model, where we estimate the components as functions of the phenotype y. Furthermore, our model allows switching, for instance, from the ACE model to the ADE model within the range of the same phenotype. When applied to birth weight (BW) data on Norwegian mother-father-child trios, we conclude from the model that low and high BW are less heritable traits than medium BW. We also demonstrate switching between the ACE and ADE model when studying body mass index in adult monozygotic and dizygotic twins.
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Affiliation(s)
- Geir D Berentsen
- Department of Business and Management Science, NHH Norwegian School of Economics, Bergen, Norway
| | | | - Hans J Skaug
- Department of Mathematics, University of Bergen, Bergen, Norway
| | - Rolv T Lie
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Håkon K Gjessing
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
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21
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Arbet J, McGue M, Basu S. A robust and unified framework for estimating heritability in twin studies using generalized estimating equations. Stat Med 2020; 39:3897-3913. [PMID: 32449216 DOI: 10.1002/sim.8564] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 03/13/2020] [Accepted: 04/10/2020] [Indexed: 11/11/2022]
Abstract
The 'heritability' of a phenotype measures the proportion of trait variance due to genetic factors in a population. In the past 50 years, studies with monozygotic and dizygotic twins have estimated heritability for 17,804 traits;1 thus twin studies are popular for estimating heritability. Researchers are often interested in estimating heritability for non-normally distributed outcomes such as binary, counts, skewed or heavy-tailed continuous traits. In these settings, the traditional normal ACE model (NACE) and Falconer's method can produce poor coverage of the true heritability. Therefore, we propose a robust generalized estimating equations (GEE2) framework for estimating the heritability of non-normally distributed outcomes. The traditional NACE and Falconer's method are derived within this unified GEE2 framework, which additionally provides robust standard errors. Although the traditional Falconer's method cannot adjust for covariates, the corresponding 'GEE2-Falconer' can incorporate mean and variance-level covariate effects (e.g. let heritability vary by sex or age). Given a non-normally distributed outcome, the GEE2 models are shown to attain better coverage of the true heritability compared to traditional methods. Finally, a scenario is demonstrated where NACE produces biased estimates of heritability while Falconer remains unbiased. Therefore, we recommend GEE2-Falconer for estimating the heritability of non-normally distributed outcomes in twin studies.
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Affiliation(s)
- Jaron Arbet
- Department of Biostatistics and Informatics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Matt McGue
- Department of Psychology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Saonli Basu
- Department of Biostatistics, University of Minnesota, Minneapolis, Minnesota, USA
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22
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Huo Z, Rana BK, Elman JA, Dong R, Engelman CD, Johnson SC, Lyons MJ, Franz CE, Kremen WS, Zhao J. Metabolic Profiling of Cognitive Aging in Midlife. Front Aging Neurosci 2020; 12:555850. [PMID: 33250761 PMCID: PMC7674168 DOI: 10.3389/fnagi.2020.555850] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 10/16/2020] [Indexed: 01/08/2023] Open
Abstract
Alzheimer's dementia (AD) begins many years before its clinical symptoms. Metabolic dysfunction represents a core feature of AD and cognitive impairment, but few metabolomic studies have focused on cognitive aging in midlife. Using an untargeted metabolomics approach, we identified metabolic predictors of cognitive aging in midlife using fasting plasma sample from 30 middle-aged (mean age 57.2), male-male twin pairs enrolled in the Vietnam Era Twin Study of Aging (VETSA). For all twin pairs, one twin developed incident MCI, whereas his co-twin brother remained to be cognitively normal during an average 5.5-year follow-up. Linear mixed model was used to identify metabolites predictive of MCI conversion or cognitive change over time, adjusting for traditional risk factors. Results from twins were replicated in an independent cohort of middle-aged adults (mean age 59.1) in the Wisconsin Registry for Alzheimer's Prevention (WRAP). Results in twins showed that higher baseline levels of four plasma metabolites, including sphingomyelin (d18:1/20:1 and d18:2/20:0), sphingomyelin (d18:1/22:1, d18:2/22:0, and d16:1/24:1), DAG (18:2/20:4), and hydroxy-CMPF, were significantly associated with a slower decrease in one or more domains of cognitive function. The association of sphingomyelin (d18:1/20:1 and d18:2/20:0) was replicated in WRAP. Our results support that metabolic perturbation occurs many years before cognitive impairment and plasma metabolites may serve as early biomarkers for prediction or monitoring of cognitive aging and AD in midlife.
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Affiliation(s)
- Zhiguang Huo
- Department of Biostatistics, University of Florida, Gainesville, FL, United States
| | - Brinda K. Rana
- Department of Psychiatry, University of California, San Diego, San Diego, CA, United States
| | - Jeremy A. Elman
- Department of Psychiatry, University of California, San Diego, San Diego, CA, United States
| | - Ruocheng Dong
- Population Health Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Corinne D. Engelman
- Population Health Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Wisconsin Alzheimer’s Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Sterling C. Johnson
- Wisconsin Alzheimer’s Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Michael J. Lyons
- Department of Psychological & Brain Sciences, Boston University, Boston, MA, United States
| | - Carol E. Franz
- Department of Psychiatry, University of California, San Diego, San Diego, CA, United States
| | - William S. Kremen
- Department of Psychiatry, University of California, San Diego, San Diego, CA, United States
- Center of Excellence for Stress and Mental Health, Veterans Affairs San Diego Healthcare System, San Diego, CA, United States
| | - Jinying Zhao
- Department of Epidemiology, University of Florida, Gainesville, FL, United States
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23
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Abstract
A comprehensive review of the body of genetic studies on schizophrenia seems even more daunting than the battle a psychiatrist wages daily in the office with her archenemy of a thousand faces. The following article reunites some genetic, epigenetic and environmental factors of schizophrenia from revered and vast studies in a chronological and progressive fashion. Twin studies set the basics of heritability and a particular study by Davis and Phelps considers the widely ignored influence of prenatal environment in the development of schizophrenia. Mostly ignited by linkage studies, candidate gene studies explore further by fine-mapping the hypothesized variants [mostly in the forms single nucleotide polymorphisms (SNPs) and less but with greater impact copy number variations (CNVs)] associated with the disease. Genome-wide association studies (GWAS) increase considerably the sample sizes and thus the validity of the results, while the next-generation sequencing (NGS) attain the highest yet unreplicated level of validity results.
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Affiliation(s)
- Simona Corina Trifu
- Department of Neurosciences, 'Carol Davila' University of Medicine and Pharmacy, 020021 Bucharest, Romania
| | - Bianca Kohn
- Department of Psychiatry, 'Prof. Dr. Alexandru Obregia' Clinical Hospital of Psychiatry, 041914 Bucharest, Romania
| | - Andrei Vlasie
- Department of Psychiatry, 'Prof. Dr. Alexandru Obregia' Clinical Hospital of Psychiatry, 041914 Bucharest, Romania
| | - Bogdan-Eduard Patrichi
- Department of Psychiatry and Psychology, 'Carol Davila' University of Medicine and Pharmacy, 020021 Bucharest, Romania
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24
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Slutske WS, Lind PA. Contributions of Nicholas Martin to Gambling Disorder Research. Twin Res Hum Genet 2020; 23:127-8. [PMID: 32423511 DOI: 10.1017/thg.2020.34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Professor Nicholas G. Martin, from QIMR Berghofer Medical Research Institute in Brisbane, Australia, is a world leader in the effort to understand the genetic architecture underlying disordered gambling. This article pays tribute to Nick and his almost two decades of gambling research, highlighting his many strengths, ranging from the use of ingenious recruitment approaches, twin study methods, genomewide association studies, to facilitating international collaborations.
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25
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Winiger EA, Huggett SB, Hatoum AS, Friedman NP, Drake CL, Wright KP, Hewitt JK. Onset of regular cannabis use and young adult insomnia: an analysis of shared genetic liability. Sleep 2020; 43:zsz293. [PMID: 31855253 PMCID: PMC7368342 DOI: 10.1093/sleep/zsz293] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 11/22/2019] [Indexed: 01/13/2023] Open
Abstract
STUDY OBJECTIVES Estimate the genetic and environmental influences on the relationship between onset of regular cannabis use and young adult insomnia. METHODS In a population-based twin cohort of 1882 twins (56% female, mean age = 22.99, SD = 2.97) we explored the genetic/environmental etiology of the relationship between onset of regular cannabis use and insomnia-related outcomes via multivariate twin models. RESULTS Controlling for sex, current depression symptoms, and prior diagnosis of an anxiety or depression disorder, adult twins who reported early onset for regular cannabis use (age 17 or younger) were more likely to have insomnia (β = 0.07, p = 0.024) and insomnia with short sleep on weekdays (β = 0.08, p = 0.003) as young adults. We found significant genetic contributions for the onset of regular cannabis use (a2 = 76%, p < 0.001), insomnia (a2 = 44%, p < 0.001), and insomnia with short sleep on weekdays (a2 = 37%, p < 0.001). We found significant genetic correlations between onset of regular use and both insomnia (rA = 0.20, p = 0.047) and insomnia with short sleep on weekdays (rA = 0.25, p = 0.008) but no significant environmental associations between these traits. CONCLUSIONS We found common genetic liabilities for early onset of regular cannabis use and insomnia, implying pleiotropic influences of genes on both traits.
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Affiliation(s)
- Evan A Winiger
- Institute for Behavioral Genetics, University of Colorado - Boulder, Boulder, CO
- Department of Psychology and Neuroscience, University of Colorado - Boulder, Boulder, CO
| | - Spencer B Huggett
- Institute for Behavioral Genetics, University of Colorado - Boulder, Boulder, CO
- Department of Psychology and Neuroscience, University of Colorado - Boulder, Boulder, CO
| | - Alexander S Hatoum
- Institute for Behavioral Genetics, University of Colorado - Boulder, Boulder, CO
- Department of Psychology and Neuroscience, University of Colorado - Boulder, Boulder, CO
| | - Naomi P Friedman
- Institute for Behavioral Genetics, University of Colorado - Boulder, Boulder, CO
- Department of Psychology and Neuroscience, University of Colorado - Boulder, Boulder, CO
| | | | - Kenneth P Wright
- Department of Integrative Physiology, University of Colorado - Boulder, Boulder, CO
| | - John K Hewitt
- Institute for Behavioral Genetics, University of Colorado - Boulder, Boulder, CO
- Department of Psychology and Neuroscience, University of Colorado - Boulder, Boulder, CO
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Brandsma FL, Spruijt MS, Rijken M, Tan RNGB, Oepkes D, Lopriore E, van Klink JMM. Behavioural outcome in twin-twin transfusion syndrome survivors treated with laser surgery. Arch Dis Child Fetal Neonatal Ed 2020; 105:304-309. [PMID: 31371433 DOI: 10.1136/archdischild-2019-317080] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 11/04/2022]
Abstract
OBJECTIVE Evaluate the incidence of and risk factors for behavioural problems in twin-twin transfusion syndrome (TTTS) survivors treated with fetoscopic laser coagulation. DESIGN Observational cohort study. SETTING National referral center for fetal therapy, Leiden University Medical Center, The Netherlands. PATIENTS Behavioural outcome was assessed in 417 TTTS survivors, at the age of 2 years. INTERVENTIONS Parents completed the Child Behavior Checklist for their twins. Antenatal, neonatal and follow-up data including Bayley III and a neurological exam were recorded from the medical database. MAIN OUTCOME MEASURES The incidence of and risk factors for behavioural problems. RESULTS 332 twin pregnancies (664 fetuses) were treated with fetoscopic laser for TTTS between 2008 and 2015. For 517 children eligible for follow-up, 417 (81%) Child Behavior Checklist questionnaires were completed. The study group was born at a mean gestational age of 32.8 weeks±3.2. Total behavioural problems within the borderline to clinical range were reported in 8% (95% CI 5.9 to 11.2) of survivors, compared with 10% in the general Dutch population (p=0.12). No difference between donors and recipients was detected (p=0.84). Internalising and externalising problems were reported in 9.4% (95% CI 6.9 to 12.6) and 11.5% (95% CI 8.8 to 15.0), respectively. Severe neurodevelopmental impairment was more frequent in the children with behavioural problems. High maternal educational level was associated with lower behavioural problem scores. CONCLUSION Parents of twins treated with fetoscopic laser therapy for TTTS do not report more behavioural problems compared with general population norms. More behavioural problems are reported in children with severe neurodevelopmental impairment.
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Affiliation(s)
- Fieke L Brandsma
- Pediatrics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Monique Rijken
- Pediatrics, Leiden University Medical Center, Leiden, The Netherlands
| | - Ratna N G B Tan
- Neonatology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Dick Oepkes
- Obstetrics, Leiden University Medical Center, Leiden, The Netherlands
| | - Enrico Lopriore
- Neonatology, Leiden University Medical Centre, Leiden, The Netherlands
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Honda C, Watanabe M, Tomizawa R, Sakai N; Osaka Twin Research Group. Update on Osaka University Twin Registry: An Overview of Multidisciplinary Research Resources and Biobank at Osaka University Center for Twin Research. Twin Res Hum Genet 2019; 22:597-601. [PMID: 31910931 DOI: 10.1017/thg.2019.70] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The Osaka University Twin Registry was originally established as a registry of older twins but was subsequently expanded to include twins of all ages. The Center for Twin Research at Osaka University Graduate School of Medicine has been managing this registry, as well as collecting research information and bioresources from twin participants. Based on the resources, multidisciplinary research projects have been conducted in collaboration with researchers from institutions both inside and outside Japan. One of the main aims of the center is to collect research information as well as biological resources from registered twins, and to establish a biobank and databases of these data and bioresources. Although data availability may vary, the following data have been collected: physical data (e.g., height, body weight, blood pressure, theoretical visceral fat, pulse wave velocity and bone density); epidemiological data (e.g., medical history, lifestyle, quality of life, mood status, cognitive function and nutritional status); electrocardiography, ultrasonography (carotid artery and thyroid); dentistry, dermatological assessment; positron emission tomography; magnetoencephalographam; brain magnetic resonance imaging (MRI); and functional MRI. In addition to these in-person survey data, microbiome data have been collected from some participants. As for bioresources, peripheral blood is obtained from the participants for isolation of serum and extraction of DNA and RNA, then stored in deep freezers for further analyses. A variety of research projects are in progress and more are on the way both in Japan and internationally using these data.
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Mittal R, Sanchez-Luege SV, Wagner SM, Yan D, Liu XZ. Recent Perspectives on Gene-Microbe Interactions Determining Predisposition to Otitis Media. Front Genet 2019; 10:1230. [PMID: 31850076 PMCID: PMC6901973 DOI: 10.3389/fgene.2019.01230] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/06/2019] [Indexed: 01/15/2023] Open
Abstract
A comprehensive understanding about the pathogenesis of otitis media (OM), one of the most common pediatric diseases, has the potential to alleviate a substantial disease burden across the globe. Advancements in genetic and bioinformatic detection methods, as well as a growing interest in the microbiome, has enhanced the capability of researchers to investigate the interplay between host genes, host microbiome, invading bacteria, and resulting OM susceptibility. Early studies deciphering the role of genetics in OM susceptibility assessed the heritability of the phenotype in twin and triplet studies, followed by linkage studies, candidate gene approaches, and genome-wide association studies that have helped in the identification of specific loci. With the advancements in techniques, various chromosomal regions and genes such as FBXO11, TGIF1, FUT2, FNDC1, and others have been implicated in predisposition to OM, yet questions still remain as to whether these implicated genes truly play a causative role in OM and to what extent. Meanwhile, 16S ribosomal RNA (rRNA) sequencing, microbial quantitative trait loci (mbQTL), and microbial genome-wide association studies (mGWAS) have mapped the microbiome of upper airways sites and therefore helped in enabling a more detailed study of interactions between host polymorphisms and host microbiome composition. Variants of specific genes conferring increased OM susceptibility, such as A2ML1, have also been shown to influence the microbial composition of the outer and middle ear in patients with OM, suggesting their role as mediators of disease. These interactions appear to impact the colonization of known otopathogens (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis), as well as Neisseria, Gemella, Porphyromonas, Alloprevotella, and Fusobacterium populations that have also been implicated in OM pathogenesis. Meanwhile, studies demonstrating an increased abundance of Dolosigranulum and Corynebacterium in healthy patients compared to those with OM suggest a protective role for these bacteria, thereby introducing potential avenues for future probiotic treatment. Incorporating insights from these genetic, microbiome, and host-pathogen studies will allow for a more robust, comprehensive understanding of OM pathogenesis that can ultimately facilitate in the development of exciting new treatment modalities.
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Affiliation(s)
- Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Sebastian V Sanchez-Luege
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Shannon M Wagner
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States.,Department of Pediatrics, University of Miami Miller School of Medicine, Miami, FL, United States.,Dr. John T. Macdonald Foundation, Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, FL, United States
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Feng G, Zhou B, Zhou W, Beauchamp MS, Magnotti JF. A Laboratory Study of the McGurk Effect in 324 Monozygotic and Dizygotic Twins. Front Neurosci 2019; 13:1029. [PMID: 31636529 PMCID: PMC6787151 DOI: 10.3389/fnins.2019.01029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/10/2019] [Indexed: 11/13/2022] Open
Abstract
Multisensory integration of information from the talker's voice and the talker's mouth facilitates human speech perception. A popular assay of audiovisual integration is the McGurk effect, an illusion in which incongruent visual speech information categorically changes the percept of auditory speech. There is substantial interindividual variability in susceptibility to the McGurk effect. To better understand possible sources of this variability, we examined the McGurk effect in 324 native Mandarin speakers, consisting of 73 monozygotic (MZ) and 89 dizygotic (DZ) twin pairs. When tested with 9 different McGurk stimuli, some participants never perceived the illusion and others always perceived it. Within participants, perception was similar across time (r = 0.55 at a 2-year retest in 150 participants) suggesting that McGurk susceptibility reflects a stable trait rather than short-term perceptual fluctuations. To examine the effects of shared genetics and prenatal environment, we compared McGurk susceptibility between MZ and DZ twins. Both twin types had significantly greater correlation than unrelated pairs (r = 0.28 for MZ twins and r = 0.21 for DZ twins) suggesting that the genes and environmental factors shared by twins contribute to individual differences in multisensory speech perception. Conversely, the existence of substantial differences within twin pairs (even MZ co-twins) and the overall low percentage of explained variance (5.5%) argues against a deterministic view of individual differences in multisensory integration.
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Affiliation(s)
- Guo Feng
- CAS Key Laboratory of Behavioral Science, Institute of Psychology, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
- Psychological Research and Counseling Center, Southwest Jiaotong University, Chengdu, China
| | - Bin Zhou
- CAS Key Laboratory of Behavioral Science, Institute of Psychology, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Wen Zhou
- CAS Key Laboratory of Behavioral Science, Institute of Psychology, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Michael S. Beauchamp
- Department of Neurosurgery and Core for Advanced MRI, Baylor College of Medicine, Houston, TX, United States
| | - John F. Magnotti
- Department of Neurosurgery and Core for Advanced MRI, Baylor College of Medicine, Houston, TX, United States
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Medda E, Toccaceli V, Fagnani C, Nisticò L, Brescianini S, Salemi M, Ferri M, D'Ippolito C, Alviti S, Arnofi A, Stazi MA. The Italian Twin Registry: An Update at 18 Years From Its Inception. Twin Res Hum Genet 2019; 22:572-8. [PMID: 31554534 DOI: 10.1017/thg.2019.75] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The Italian Twin Registry (ITR), established in 2001, is a population-based registry of voluntary twins. To date, it consists of approximately 29,000 twins who gave their consent to participate in the studies proposed by the ITR research group. The database comprises 11,500 monozygotic and 16,700 dizygotic twins resident throughout the country and belonging to a wide age range (from 0 to 95 years, mean 36.8 years). This article provides an overview of the recruitment strategies along with the major phenotypes investigated during an 18 years' research period. Over the years, several self-reported questionnaire data were collected, together with saliva/blood samples and measurements taken during in-person interviews or outpatient clinical examinations. Mental and behavioral phenotypes as well as atherosclerotic traits were studied in depth across different age groups. A birth cohort of twins was established and followed up. Novel research hypotheses are also being tested in ongoing projects. The ITR is involved in international studies in collaboration with other twin registries and represents a valuable resource for national and international research initiatives regarding a broad spectrum of health-related characteristics.
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Rimfeld K, Malanchini M, Spargo T, Spickernell G, Selzam S, McMillan A, Dale PS, Eley TC, Plomin R. Twins Early Development Study: A Genetically Sensitive Investigation into Behavioral and Cognitive Development from Infancy to Emerging Adulthood. Twin Res Hum Genet 2019; 22:508-13. [PMID: 31544730 DOI: 10.1017/thg.2019.56] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The Twins Early Development Study (TEDS) is a longitudinal twin study that recruited over 16,000 twin-pairs born between 1994 and 1996 in England and Wales through national birth records. More than 10,000 of these families are still engaged in the study. TEDS was and still is a representative sample of the population in England and Wales. Rich cognitive and emotional/behavioral data have been collected from the twins from infancy to emerging adulthood, with data collection at first contact and at ages 2, 3, 4, 7, 8, 9, 10, 12, 14, 16, 18 and 21, enabling longitudinal genetically sensitive analyses. Data have been collected from the twins themselves, from their parents and teachers, and from the UK National Pupil Database. Genotyped DNA data are available for 10,346 individuals (who are unrelated except for 3320 dizygotic co-twins). TEDS data have contributed to over 400 scientific papers involving more than 140 researchers in 50 research institutions. TEDS offers an outstanding resource for investigating cognitive and behavioral development across childhood and early adulthood and actively fosters scientific collaborations.
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32
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Ordoñana JR, Carrillo E, Colodro-Conde L, García-Palomo FJ, González-Javier F, Madrid-Valero JJ, Martínez Selva JM, Monteagudo O, Morosoli JJ, Pérez-Riquelme F, Sánchez-Romera JF. An Update of Twin Research in Spain: The Murcia Twin Registry. Twin Res Hum Genet 2019; 22:667-71. [PMID: 31500683 DOI: 10.1017/thg.2019.60] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The Murcia Twin Registry (MTR) is the only population-based registry in Spain. Created in 2006, the registry has been growing more than a decade to become one of the references for twin research in the Mediterranean region. The MTR database currently comprises 3545 adult participants born between 1940 and 1977. It also holds a recently launched satellite registry of university students (N = 204). Along five waves of data collection, the registry has gathered questionnaire and anthropometric data, as well as biological samples. The MTR keeps its main research focus on health and health-related behaviors from a public health perspective. This includes lifestyle, health promotion, quality of life or environmental conditions. Future short-term development points to the expansion of the biobank and the continuation of the collection of longitudinal data.
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Phamduong S, Kim CS. Presentation of Localized Aggressive Periodontitis in Monozygotic Twins: Case Report. Clin Adv Periodontics 2019; 9:9-14. [PMID: 31490033 DOI: 10.1002/cap.10041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 04/02/2018] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Localized aggressive periodontal disease is an uncommon finding observed in adolescents and children. Studies have been conducted to elucidate the etiology, contributing factors, and genetic roles in the phenomena. In particular, twin studies have shown genetic makeup to be a substantial risk factor for periodontitis. This case is, to the best of the authors' knowledge, the first to be presented in literature of a same dwelling, set of monozygotic twins, displaying similar presentation of localized aggressive periodontitis, however with different microbial profiles. CASE PRESENTATION A set of 17-year-old black male monozygotic twins were referred for a full-mouth periodontal evaluation and any necessary periodontal treatment on July 7, 2007. A full-mouth radiographic series, periodontal charting, and intraoral photographs were performed on each individual. A family history was obtained through the biological mother, which yielded no known history of early tooth loss or treatment of severe periodontal disease. The father was not involved in the rearing of the children and his periodontal history was unavailable. An initial and surgical treatment plan was developed. Microbial analysis of subgingival plaque samples was collected on the affected sites. Initial treatment with scaling and root planing, subgingival irrigation, with administration of systemic antibiotics, and oral hygiene instruction, were rendered on both individuals. CONCLUSION Within limitations of this report, it is demonstrated that different microbial pattern exists on aggressive periodontitis even in genetically identical individuals with the same environmental exposure.
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Affiliation(s)
| | - Clara S Kim
- Department of Periodontics, Western University of Health Sciences, College of Dental Medicine, Pomona, CA
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Abstract
It has been over 5 years since the last special issue of Twin Research and Human Genetics on 'Twin Registries Worldwide: An Important Resource for Scientific Research' was published. Much progress has been made in the broad field of twin research since that time, and the current special issue is a follow-up to update the scientific community about twin registries around the globe. The present article builds upon our 2013 Registry description by summarizing current information on the Washington State Twin Registry (WSTR), including history and construction methods, member characteristics, available data, and major research goals. We also provide a section with brief summaries of recently completed studies and discuss the future research directions of the WSTR. The Registry has grown in terms of size and scope since 2013; highlights include recruitment of youth pairs under 18 years of age, extensive geocoding work to develop environmental exposures that can be linked to survey and administrative health data such as death records, and expansion of a biobank with specimens collected for genotyping, DNA methylation, and microbiome based-studies.
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Torvik FA, Rosenström TH, Gustavson K, Ystrom E E, Kendler KS, Bramness JG, Czajkowski N, Reichborn-Kjennerud T. Explaining the association between anxiety disorders and alcohol use disorder: A twin study. Depress Anxiety 2019; 36:522-532. [PMID: 30838764 PMCID: PMC6548587 DOI: 10.1002/da.22886] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 01/23/2019] [Accepted: 02/02/2019] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND It is unknown whether social anxiety disorder (SAD) has a unique association with alcohol use disorder (AUD) over and beyond that of other anxiety disorders, how the associations develop over time, and whether the associations are likely to be causal. METHODS Diagnoses of AUD, SAD, generalized anxiety disorder, panic disorder, agoraphobia, and specific phobias were assessed twice using the Composite International Diagnostic Interview among 2,801 adult Norwegian twins. The data were analyzed using logistic regression analyses and multivariate biometric structural equation modeling. RESULTS SAD had the strongest association with AUD, and SAD predicted AUD over and above the effect of other anxiety disorders. In addition, SAD was prospectively associated with AUD, whereas other anxiety disorders were not. AUD was associated with a slightly elevated risk of later anxiety disorders other than SAD. Biometric modeling favored a model where SAD influenced AUD compared to models where the relationship was reversed or due to correlated risk factors. Positive associations between AUD and other anxiety disorders were fully explained by shared genetic risk factors. CONCLUSIONS Unlike other anxiety disorders, SAD plausibly has a direct effect on AUD. Interventions aimed at prevention or treatment of SAD may have an additional beneficial effect of preventing AUD, whereas interventions aimed at other anxiety disorders are unlikely to have a similar sequential effect on AUD.
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Affiliation(s)
- Fartein Ask Torvik
- Department of Mental Disorders, Norwegian Institute of Public Health, Oslo, Norway;,Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway;,Department of Psychology, University of Oslo, Norway
| | | | - Kristin Gustavson
- Department of Mental Disorders, Norwegian Institute of Public Health, Oslo, Norway;,Department of Psychology, University of Oslo, Norway
| | - Eivind Ystrom E
- Department of Mental Disorders, Norwegian Institute of Public Health, Oslo, Norway;,Department of Psychology, University of Oslo, Norway;,PharmacoEpidemiology and Drug Safety Research Group, School of Pharmacy, University of Oslo, Norway
| | - Kenneth S. Kendler
- Virginia Institute for Psychiatric and Behavioral Genetics, Department of Psychiatry, Virginia Commonwealth University, Richmond, VA, USA;,Department of Human and Molecular Genetics and Department of Psychiatry, Virginia Commonwealth University, Richmond, VA, USA
| | - Jørgen G. Bramness
- Norwegian National Advisory Unit on Concurrent Substance Abuse and Mental Health Disorders, Brumunddal, Norway;,Institute of Clinical Medicine, UiT - The Arctic University of Norway
| | - Nikolai Czajkowski
- Department of Mental Disorders, Norwegian Institute of Public Health, Oslo, Norway;,Department of Psychology, University of Oslo, Norway
| | - Ted Reichborn-Kjennerud
- Department of Mental Disorders, Norwegian Institute of Public Health, Oslo, Norway;,Institute of Clinical Medicine, University of Oslo, Norway
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Chen X, Formisano E, Blokland GAM, Strike LT, McMahon KL, de Zubicaray GI, Thompson PM, Wright MJ, Winkler AM, Ge T, Nichols TE. Accelerated estimation and permutation inference for ACE modeling. Hum Brain Mapp 2019; 40:3488-3507. [PMID: 31037793 PMCID: PMC6680147 DOI: 10.1002/hbm.24611] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 04/15/2019] [Accepted: 04/17/2019] [Indexed: 11/30/2022] Open
Abstract
There are a wealth of tools for fitting linear models at each location in the brain in neuroimaging analysis, and a wealth of genetic tools for estimating heritability for a small number of phenotypes. But there remains a need for computationally efficient neuroimaging genetic tools that can conduct analyses at the brain‐wide scale. Here we present a simple method for heritability estimation on twins that replaces a variance component model‐which requires iterative optimisation‐with a (noniterative) linear regression model, by transforming data to squared twin‐pair differences. We demonstrate that the method has comparable bias, mean squared error, false positive risk, and power to best practice maximum‐likelihood‐based methods, while requiring a small fraction of the computation time. Combined with permutation, we call this approach “Accelerated Permutation Inference for the ACE Model (APACE)” where ACE refers to the additive genetic (A) effects, and common (C), and unique (E) environmental influences on the trait. We show how the use of spatial statistics like cluster size can dramatically improve power, and illustrate the method on a heritability analysis of an fMRI working memory dataset.
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Affiliation(s)
- Xu Chen
- Department of Statistics, University of Warwick, Coventry, UK.,Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, the Netherlands.,Maastricht Centre for Systems Biology (MaCSBio), Maastricht University, Maastricht, the Netherlands.,Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, the Netherlands
| | - Elia Formisano
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, the Netherlands.,Maastricht Centre for Systems Biology (MaCSBio), Maastricht University, Maastricht, the Netherlands
| | - Gabriëlla A M Blokland
- Psychiatric and Neurodevelopmental Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts.,Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Lachlan T Strike
- Queensland Brain Institute, University of Queensland, Brisbane, Queensland, Australia
| | - Katie L McMahon
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - Greig I de Zubicaray
- Faculty of Health and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Paul M Thompson
- Imaging Genetics Center, University of Southern California, Los Angeles, California
| | - Margaret J Wright
- Queensland Brain Institute, University of Queensland, Brisbane, Queensland, Australia.,Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - Anderson M Winkler
- Emotion and Development Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland.,Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Tian Ge
- Psychiatric and Neurodevelopmental Genetics Unit, Center for Genomic Medicine, Massachusetts General Hospital, Boston, Massachusetts.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts.,Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts
| | - Thomas E Nichols
- Department of Statistics, University of Warwick, Coventry, UK.,Oxford Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Population Health, University of Oxford, Oxford, UK
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Tosto MG, Garon-Carrier G, Gross S, Petrill SA, Malykh S, Malki K, Hart SA, Thompson L, Karadaghi RL, Yakovlev N, Tikhomirova T, Opfer JE, Mazzocco MMM, Dionne G, Brendgen M, Vitaro F, Tremblay RE, Boivin M, Kovas Y. The nature of the association between number line and mathematical performance: An international twin study. Br J Educ Psychol 2018; 89:787-803. [PMID: 30548254 DOI: 10.1111/bjep.12259] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 10/29/2018] [Indexed: 01/29/2023]
Abstract
BACKGROUND The number line task assesses the ability to estimate numerical magnitudes. People vary greatly in this ability, and this variability has been previously associated with mathematical skills. However, the sources of individual differences in number line estimation and its association with mathematics are not fully understood. AIMS This large-scale genetically sensitive study uses a twin design to estimate the magnitude of the effects of genes and environments on: (1) individual variation in number line estimation and (2) the covariation of number line estimation with mathematics. SAMPLES We used over 3,000 8- to 16-year-old twins from the United States, Canada, the United Kingdom, and Russia, and a sample of 1,456 8- to 18-year-old singleton Russian students. METHODS Twins were assessed on: (1) estimation of numerical magnitudes using a number line task and (2) two mathematics components: fluency and problem-solving. RESULTS Results suggest that environments largely drive individual differences in number line estimation. Both genes and environments contribute to different extents to the number line estimation and mathematics correlation, depending on the sample and mathematics component. CONCLUSIONS Taken together, the results suggest that in more heterogeneous school settings, environments may be more important in driving variation in number line estimation and its association with mathematics, whereas in more homogeneous school settings, genetic effects drive the covariation between number line estimation and mathematics. These results are discussed in the light of development and educational settings.
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Affiliation(s)
- Maria Grazia Tosto
- Laboratory for Cognitive Investigations and Behavioral Genetics, Department of Psychology, Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Oblast, Russia
| | | | - Susan Gross
- Department of Psychological Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Stephen A Petrill
- Department of Psychology, The Ohio State University, Columbus, Ohio, USA
| | - Sergey Malykh
- Laboratory for Cognitive Investigations and Behavioral Genetics, Department of Psychology, Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Oblast, Russia.,Psychological Institute, Russian Academy of Education, Moscow, Russia
| | - Karim Malki
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology& Neuroscience, King's College London, UK
| | - Sara A Hart
- Department of Psychology, Florida Center for Reading Research, The Florida State University, Tallahassee, Florida, USA
| | - Lee Thompson
- Department of Psychological Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Rezhaw L Karadaghi
- MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology& Neuroscience, King's College London, UK
| | - Nikita Yakovlev
- Laboratory for Cognitive Investigations and Behavioral Genetics, Department of Psychology, Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Oblast, Russia
| | | | - John E Opfer
- Department of Psychology, The Ohio State University, Columbus, Ohio, USA
| | - Michèle M M Mazzocco
- Institute of Child Development, University of Minnesota, Minneapolis, Minnesota, USA
| | - Ginette Dionne
- School of Psychology, Université Laval, Québec City, Québec, Canada
| | - Mara Brendgen
- Department of Psychology, School of Psychology, Université du Québec à Montréal, Québec, Canada
| | - Frank Vitaro
- Department of Psychoeducation, Department of Pediatrics and Psychology, Université de Montréal, Québec, Canada
| | - Richard E Tremblay
- Laboratory for Cognitive Investigations and Behavioral Genetics, Department of Psychology, Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Oblast, Russia.,Department of Psychoeducation, Department of Pediatrics and Psychology, Université de Montréal, Québec, Canada.,School of Public Health, Physiotherapy and Sports Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Michel Boivin
- Laboratory for Cognitive Investigations and Behavioral Genetics, Department of Psychology, Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Oblast, Russia.,School of Psychology, Université Laval, Québec City, Québec, Canada
| | - Yulia Kovas
- Laboratory for Cognitive Investigations and Behavioral Genetics, Department of Psychology, Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Oblast, Russia.,MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology& Neuroscience, King's College London, UK.,Department of Psychology, University of London, UK
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Jarrar ZA, Ward KJ, Mangino M, Cherkas LF, Gill R, Gillham-Nasenya I, Yarand D, Hart D, Hammond CJ, Spector TD. Definitive Zygosity Scores in the Peas in the Pod Questionnaire is a Sensitive and Accurate Assessment of the Zygosity of Adult Twins. Twin Res Hum Genet 2018; 21:146-54. [PMID: 29582724 DOI: 10.1017/thg.2018.9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Twin researchers face the challenge of accurately determining the zygosity of twins for research. As part of the annual questionnaire between 1999 and 2006, 8,307 twins from the TwinsUK registry were asked to complete five questions (independently from their co-twin) to ascertain their self-perceived zygosity during childhood on up to five separate occasions. This questionnaire is known as the 'peas in the pod' questionnaire (PPQ), but there is little evidence of its validation. Answers were scored and classified as monozygotic (MZ), dizygotic (DZ), or unknown zygosity (UZ) and were compared with 4,484 twins with genotyping data who had not been selected for zygosity. Of these, 3,859 individuals (46.5% of those who had a zygosity from PPQ) had zygosity classified by both the PPQ and genotyping. Of the 708 individual twins whose answers meant that they were consistently classed as MZ in the PPQ, 683 (96.5%) were MZ within the genotype data. Of the 945 individual twins consistently classed as DZ within questionnaire, 936 (99.0%) were DZ in the genotype data. Where both twins scored MZ consistently across multiple questionnaires, 99.6% were MZ on genotyping, 99.7% were DZ on genotyping if both twins consistently scored DZ. However, for the initial questionnaire, 88.6% of those scoring as MZ were genotypically MZ and 98.7% DZ. For twin pairs where both scored UZ, 94.7% were DZ. Using the PPQ on a single occasion provided a definitive classification of whether the twin was MZ or DZ with an overall accuracy of 86.9%, increasing to 97.9% when there was a consistent classification of zygosity across multiple questionnaires. This study has shown that the PPQ questionnaire is an excellent proxy indicator of zygosity in the absence of genotyping information.
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Henry J, Dionne G, Viding E, Vitaro F, Brendgen M, Tremblay RE, Boivin M. Early warm-rewarding parenting moderates the genetic contributions to callous-unemotional traits in childhood. J Child Psychol Psychiatry 2018; 59:1282-1288. [PMID: 29683187 DOI: 10.1111/jcpp.12918] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/13/2018] [Indexed: 11/30/2022]
Abstract
BACKGROUND Previous gene-environment interaction studies of CU traits have relied on the candidate gene approach, which does not account for the entire genetic load of complex phenotypes. Moreover, these studies have not examined the role of positive environmental factors such as warm/rewarding parenting. The aim of the present study was to determine whether early warm/rewarding parenting moderates the genetic contributions (i.e., heritability) to callous-unemotional (CU) traits at school age. METHODS Data were collected in a population sample of 662 twin pairs (Quebec Newborn Twin Study - QNTS). Mothers reported on their warm/rewarding parenting. Teachers assessed children's CU traits. These reports were subjected to twin modeling. RESULTS Callous-unemotional traits were highly heritable, with the remaining variance accounted for by nonshared environmental factors. Warm/rewarding parenting significantly moderated the role of genes in CU traits; heritability was lower when children received high warm/rewarding parenting than when they were exposed to low warm/rewarding parenting. CONCLUSIONS High warm/rewarding parenting may partly impede the genetic expression of CU traits. Developmental models of CU traits need to account for such gene-environment processes.
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Affiliation(s)
- Jeffrey Henry
- School of Psychology, Laval University, Quebec City, QC, Canada.,Research Unit on Children's Psychosocial Maladjustment, Quebec City, QC, Canada
| | - Ginette Dionne
- School of Psychology, Laval University, Quebec City, QC, Canada.,Research Unit on Children's Psychosocial Maladjustment, Quebec City, QC, Canada
| | - Essi Viding
- Division of Psychology and Language Sciences, University College London, London, UK
| | - Frank Vitaro
- Department of Psycho-Education, University of Montreal, Montreal, QC, Canada.,Research Unit on Children's Psychosocial Maladjustment, Montreal, QC, Canada
| | - Mara Brendgen
- Department of Psychology, University of Quebec in Montreal, Montreal, QC, Canada.,Research Unit on Children's Psychosocial Maladjustment, Montreal, QC, Canada
| | - Richard E Tremblay
- Department of Psychology, University of Montreal, Montreal, QC, Canada.,Research Unit on Children's Psychosocial Maladjustment, Montreal, QC, Canada.,School of Public Health, Physiotherapy and Sports Science, University College Dublin, Dublin, Ireland
| | - Michel Boivin
- School of Psychology, Laval University, Quebec City, QC, Canada.,Research Unit on Children's Psychosocial Maladjustment, Quebec City, QC, Canada.,Institute of Genetic, Neurobiological, and Social Foundations of Child Development, Tomsk State University, Tomsk, Russia
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40
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van Bergen E, Snowling MJ, de Zeeuw EL, van Beijsterveldt CEM, Dolan CV, Boomsma DI. Why do children read more? The influence of reading ability on voluntary reading practices. J Child Psychol Psychiatry 2018; 59:1205-1214. [PMID: 29635740 DOI: 10.1111/jcpp.12910] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/12/2018] [Indexed: 11/25/2022]
Abstract
BACKGROUND This study investigates the causal relationships between reading and print exposure and investigates whether the amount children read outside school determines how well they read, or vice versa. Previous findings from behavioural studies suggest that reading predicts print exposure. Here, we use twin-data and apply the behaviour-genetic approach of direction of causality modelling, suggested by Heath et al. (), to investigate the causal relationships between these two traits. METHOD Partial data were available for a large sample of twin children (N = 11,559) and 262 siblings, all enrolled in the Netherlands Twin Register. Children were assessed around 7.5 years of age. Mothers completed questionnaires reporting children's time spent on reading activities and reading ability. Additional information on reading ability was available through teacher ratings and performance on national reading tests. For siblings reading test, results were available. RESULTS The reading ability of the twins was comparable to that of the siblings and national norms, showing that twin findings can be generalized to the population. A measurement model was specified with two latent variables, Reading Ability and Print Exposure, which correlated .41. Heritability analyses showed that Reading Ability was highly heritable, while genetic and environmental influences were equally important for Print Exposure. We exploited the fact that the two constructs differ in genetic architecture and fitted direction of causality models. The results supported a causal relationship running from Reading Ability to Print Exposure. CONCLUSIONS How much and how well children read are moderately correlated. Individual differences in print exposure are less heritable than individual differences in reading ability. Importantly, the present results suggest that it is the children's reading ability that determines how much they choose to read, rather than vice versa.
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Affiliation(s)
- Elsje van Bergen
- Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.,Experimental Psychology, University of Oxford, Oxford, UK
| | - Margaret J Snowling
- Experimental Psychology, University of Oxford, Oxford, UK.,St. John's College, Oxford, UK
| | - Eveline L de Zeeuw
- Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - Conor V Dolan
- Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Dorret I Boomsma
- Biological Psychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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Abstract
Twin studies have revealed political ideology to be partially heritable. Neurological research has shown that ideological differences are reflected in brain structure and response, suggesting a direct genotype-phenotype link. Social and informational environments, however, also demonstrably affect brain structure and response. This leads to a "chicken-and-egg" question: do genes produce brains with ideological predispositions, causing the preferential absorption of consonant information and thereby forming an ideology, or do social and informational environments do most of the heavy lifting, with genetic evidence the spurious artifact of outdated methodology? Or are both inextricably intertwined contributors? This article investigates the relative contributions of genetic and environmental factors to ideological development using a role-play experiment investigating the development of opinions on a novel political issue. The results support the view that the process is bidirectional, suggesting that, like most traits, political ideology is produced by the complex interplay of genetic and (social/informational) environmental influences.
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42
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Martin J, Taylor MJ, Lichtenstein P. Assessing the evidence for shared genetic risks across psychiatric disorders and traits. Psychol Med 2018; 48:1759-1774. [PMID: 29198204 PMCID: PMC6088770 DOI: 10.1017/s0033291717003440] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 10/26/2017] [Accepted: 10/27/2017] [Indexed: 12/21/2022]
Abstract
Genetic influences play a significant role in risk for psychiatric disorders, prompting numerous endeavors to further understand their underlying genetic architecture. In this paper, we summarize and review evidence from traditional twin studies and more recent genome-wide molecular genetic analyses regarding two important issues that have proven particularly informative for psychiatric genetic research. First, emerging results are beginning to suggest that genetic risk factors for some (but not all) clinically diagnosed psychiatric disorders or extreme manifestations of psychiatric traits in the population share genetic risks with quantitative variation in milder traits of the same disorder throughout the general population. Second, there is now evidence for substantial sharing of genetic risks across different psychiatric disorders. This extends to the level of characteristic traits throughout the population, with which some clinical disorders also share genetic risks. In this review, we summarize and evaluate the evidence for these two issues, for a range of psychiatric disorders. We then critically appraise putative interpretations regarding the potential meaning of genetic correlation across psychiatric phenotypes. We highlight several new methods and studies which are already using these insights into the genetic architecture of psychiatric disorders to gain additional understanding regarding the underlying biology of these disorders. We conclude by outlining opportunities for future research in this area.
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Affiliation(s)
- Joanna Martin
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, UK
| | - Mark J. Taylor
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Paul Lichtenstein
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
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43
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López-Solà C, Bui M, Hopper JL, Fontenelle LF, Davey CG, Pantelis C, Alonso P, van den Heuvel OA, Harrison BJ. Predictors and consequences of health anxiety symptoms: a novel twin modeling study. Acta Psychiatr Scand 2018; 137:241-251. [PMID: 29336012 DOI: 10.1111/acps.12850] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/07/2017] [Indexed: 12/20/2022]
Abstract
OBJECTIVE The question of how to best conceptualize health anxiety (HA) from a diagnostic and etiological perspective remains debated. The aim was to examine the relationship between HA and the symptoms of anxiety and obsessive-compulsive-related disorders in a normative twin population. METHOD Four hundred and ninety-six monozygotic adult twin pairs from the Australian Twin Registry participated in the study (age, 34.4 ± 7.72 years; 59% females). Validated scales were used to assess each domain. We applied a twin regression methodology-ICE FALCON-to determine whether there was evidence consistent with 'causal' relationships between HA and other symptoms by fitting and comparing model estimates. RESULTS Estimates were consistent with higher levels of obsessing ('unwanted thoughts') (P = 0.008), social anxiety (P = 0.03), and body dysmorphic symptoms (P = 0.008) causing higher levels of HA symptoms, and with higher levels of HA symptoms causing higher levels of physical/somatic anxiety symptoms (P = 0.001). CONCLUSION Obsessional thoughts, body dysmorphic concerns, and social anxiety symptoms may have a causal influence on HA. To report physical/somatic anxiety appears to be a consequence of the underlying presence of HA-related fears. Should our results be confirmed by longitudinal studies, the evaluation and treatment of HA may benefit from the consideration of these identified risk factors.
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Affiliation(s)
- C López-Solà
- Adult Mental Health Department, Parc Taulí University Hospital, Universitat Autònoma de Barcelona, Sabadell, Spain.,Carlos III Health Institute, CIBERSAM (Centro de Investigación en Red de Salud Mental), Barcelona, Spain
| | - M Bui
- Centre for Epidemiology and Biostatistics, Melbourne School of Population Health, The University of Melbourne, Melbourne, Vic, Australia
| | - J L Hopper
- Centre for Epidemiology and Biostatistics, Melbourne School of Population Health, The University of Melbourne, Melbourne, Vic, Australia.,Department of Family Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Gangnamgu, Seoul, South Korea
| | - L F Fontenelle
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, South Korea.,Instituto D'Or de Pesquisa e Ensino (IDOR), Rio de Janeiro, Brazil.,Brain & Mental Health Laboratory, Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, Vic, Australia
| | - C G Davey
- Orygen, The National Centre of Excellence in Youth Mental Health, Melbourne, Vic, Australia.,Centre for Youth Mental Health, The University of Melbourne, Melbourne, Vic, Australia.,Department of Psychiatry, Melbourne Neuropsychiatry Centre, The University of Melbourne and Melbourne Health, Melbourne, Vic, Australia
| | - C Pantelis
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, The University of Melbourne and Melbourne Health, Melbourne, Vic, Australia
| | - P Alonso
- Carlos III Health Institute, CIBERSAM (Centro de Investigación en Red de Salud Mental), Barcelona, Spain.,Department of Psychiatry, Bellvitge University Hospital, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain.,Department of Clinical Sciences, School of Medicine, University of Barcelona, Barcelona, Spain
| | - O A van den Heuvel
- Department of Anatomy and Neurosciences, VU university medical center (VUmc), Amsterdam, The Netherlands.,Department of Psychiatry, VUmc, Amsterdam, The Netherlands.,Neuroscience Campus Amsterdam, VU/VUmc, Amsterdam, The Netherlands.,The OCD team, Haukeland University Hospital, Bergen, Norway
| | - B J Harrison
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, The University of Melbourne and Melbourne Health, Melbourne, Vic, Australia
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Dick DM, Barr PB, Cho SB, Cooke ME, Kuo SIC, Lewis TJ, Neale Z, Salvatore JE, Savage J, Su J. Post-GWAS in Psychiatric Genetics: A Developmental Perspective on the "Other" Next Steps. Genes Brain Behav 2018; 17:e12447. [PMID: 29227573 PMCID: PMC5876087 DOI: 10.1111/gbb.12447] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 12/01/2017] [Accepted: 12/06/2017] [Indexed: 02/06/2023]
Abstract
As psychiatric genetics enters an era where gene identification is finally yielding robust, replicable genetic associations and polygenic risk scores, it is important to consider next steps and delineate how that knowledge will be applied to ultimately ameliorate suffering associated with substance use and psychiatric disorders. Much of the post-genome-wide association study discussion has focused on the potential of genetic information to elucidate the underlying biology and use this information for the development of more effective pharmaceutical treatments. In this review we focus on additional areas of research that should follow gene identification. By taking genetic findings into longitudinal, developmental studies, we can map the pathways by which genetic risk manifests across development, elucidating the early behavioral manifestations of risk, and studying how various environments and interventions moderate that risk across developmental stages. The delineation of risk across development will advance our understanding of mechanism, sex differences and risk and resilience processes in different racial/ethnic groups. Here, we review how the extant twin study literature can be used to guide these efforts. Together, these new lines of research will enable us to develop more informed, tailored prevention and intervention efforts.
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Affiliation(s)
- Danielle M. Dick
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | | | - Peter B. Barr
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Seung Bin Cho
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Megan E. Cooke
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Sally I-Chun Kuo
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Tenesha J. Lewis
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Zoe Neale
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Jessica E. Salvatore
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Jeanne Savage
- Department of Psychology, Developmental Program, Virginia Commonwealth University
| | - Jinni Su
- Department of Psychology, Developmental Program, Virginia Commonwealth University
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Abstract
Accurate understanding of environmental moderation of genetic influences is vital to advancing the science of cognitive development as well as for designing interventions. One widely reported idea is increasing genetic influence on cognition for children raised in higher socioeconomic status (SES) families, including recent proposals that the pattern is a particularly US phenomenon. We used matched birth and school records from Florida siblings and twins born in 1994-2002 to provide the largest, most population-diverse consideration of this hypothesis to date. We found no evidence of SES moderation of genetic influence on test scores, suggesting that articulating gene-environment interactions for cognition is more complex and elusive than previously supposed.
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Schwabe I, Janss L, van den Berg SM. Can We Validate the Results of Twin Studies? A Census-Based Study on the Heritability of Educational Achievement. Front Genet 2017; 8:160. [PMID: 29123543 PMCID: PMC5662588 DOI: 10.3389/fgene.2017.00160] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 10/10/2017] [Indexed: 11/13/2022] Open
Abstract
As for most phenotypes, the amount of variance in educational achievement explained by SNPs is lower than the amount of additive genetic variance estimated in twin studies. Twin-based estimates may however be biased because of self-selection and differences in cognitive ability between twins and the rest of the population. Here we compare twin registry based estimates with a census-based heritability estimate, sampling from the same Dutch birth cohort population and using the same standardized measure for educational achievement. Including important covariates (i.e., sex, migration status, school denomination, SES, and group size), we analyzed 893,127 scores from primary school children from the years 2008-2014. For genetic inference, we used pedigree information to construct an additive genetic relationship matrix. Corrected for the covariates, this resulted in an estimate of 85%, which is even higher than based on twin studies using the same cohort and same measure. We therefore conclude that the genetic variance not tagged by SNPs is not an artifact of the twin method itself.
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Affiliation(s)
- Inga Schwabe
- Department of Research Methodology, Measurement and Data Analysis (OMD), University of Twente, Enschede, Netherlands.,Department of Methodology and Statistics, Tilburg University, Tilburg, Netherlands
| | - Luc Janss
- Center for Quantitative Genetics and Genomics, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Stéphanie M van den Berg
- Department of Research Methodology, Measurement and Data Analysis (OMD), University of Twente, Enschede, Netherlands
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Abstract
The etiology underlying chronic widespread pain (CWP) remains largely unknown. An integrative biopsychosocial model seems to yield the most promising explanations for the pathogenesis of the condition, with genetic factors also contributing to disease development and maintenance. Here, we conducted a search of studies investigating the genetic and epigenetic epidemiology of CWP through electronic databases including Web of Science, Medline, PubMed, EMBASE, and Google Scholar. Combinations of keywords including CWP, chronic pain, musculoskeletal pain, genetics, epigenetics, gene, twins, single-nucleotide polymorphism, genotype, and alleles were used. In the end, a total of 15 publications were considered relevant to be included in this review: eight were twin studies on CWP, six were molecular genetic studies on CWP, and one was an epigenetic study on CWP. The findings suggest genetic and unique environmental factors to contribute to CWP. Various candidates such as serotonin-related pathway genes were found to be associated with CWP and somatoform symptoms. However, studies show some limitations and need replication. The presented results for CWP could serve as a template for genetic studies on other chronic pain conditions. Ultimately, a more in-depth understanding of disease mechanisms will help with the development of more effective treatment, inform nosology, and reduce the stigma still lingering on this diagnosis.
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Affiliation(s)
- Jasmine I Kerr
- Department of Psychology, University of Zurich, Zurich, Switzerland
| | - Andrea Burri
- Department of Psychology, University of Zurich, Zurich, Switzerland.,Department of Physiotherapy, Health and Rehabilitation Research Institute, Auckland University of Technology.,Waitemata Pain Service, Department of Anesthesia and Perioperative Medicine, North Shore Hospital, Auckland, New Zealand
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48
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Abstract
Using twin (6,105 twin pairs) and genomic (5,825 unrelated individuals taken from the twin sample) analyses, we tested for genetic influences on the parent-offspring correspondence in educational attainment. Genetics accounted for nearly half of the variance in intergenerational educational attainment. A genomewide polygenic score (GPS) for years of education was also associated with intergenerational educational attainment: The highest and lowest GPS means were found for offspring in stably educated families (i.e., who had taken A Levels and had a university-educated parent; M = 0.43, SD = 0.97) and stably uneducated families (i.e., who had not taken A Levels and had no university-educated parent; M = -0.19, SD = 0.97). The average GPSs fell in between for children who were upwardly mobile (i.e., who had taken A Levels but had no university-educated parent; M = 0.05, SD = 0.96) and children who were downwardly mobile (i.e., who had not taken A Levels but had a university-educated parent; M = 0.28, SD = 1.03). Genetic influences on intergenerational educational attainment can be viewed as an index of equality of educational opportunity.
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Affiliation(s)
- Ziada Ayorech
- 1 MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London
| | - Eva Krapohl
- 1 MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London
| | - Robert Plomin
- 1 MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London
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Petkus AJ, Beam CR, Johnson W, Kaprio J, Korhonen T, McGue M, Neiderhiser JM, Pedersen NL, Reynolds CA, Gatz M. Gene-environment interplay in depressive symptoms: moderation by age, sex, and physical illness. Psychol Med 2017; 47:1836-1847. [PMID: 28202098 PMCID: PMC5706656 DOI: 10.1017/s0033291717000290] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Numerous factors influence late-life depressive symptoms in adults, many not thoroughly characterized. We addressed whether genetic and environmental influences on depressive symptoms differed by age, sex, and physical illness. METHOD The analysis sample included 24 436 twins aged 40-90 years drawn from the Interplay of Genes and Environment across Multiple Studies (IGEMS) Consortium. Biometric analyses tested age, sex, and physical illness moderation of genetic and environmental variance in depressive symptoms. RESULTS Women reported greater depressive symptoms than men. After age 60, there was an accelerating increase in depressive symptom scores with age, but this did not appreciably affect genetic and environmental variances. Overlap in genetic influences between physical illness and depressive symptoms was greater in men than in women. Additionally, in men extent of overlap was greater with worse physical illness (the genetic correlation ranged from near 0.00 for the least physical illness to nearly 0.60 with physical illness 2 s.d. above the mean). For men and women, the same environmental factors that influenced depressive symptoms also influenced physical illness. CONCLUSIONS Findings suggested that genetic factors play a larger part in the association between depressive symptoms and physical illness for men than for women. For both sexes, across all ages, physical illness may similarly trigger social and health limitations that contribute to depressive symptoms.
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Affiliation(s)
- A J Petkus
- Department of Neurology,University of Southern California,Los Angeles, CA,USA
| | - C R Beam
- Department of Psychology & Davis School of Gerontology,University of Southern California,Los Angeles, CAUSA
| | - W Johnson
- Department of Psychology,Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh,Edinburgh,UK
| | - J Kaprio
- Department of Public Health,University of Helsinki,Helsinki,Finland
| | - T Korhonen
- Department of Public Health,University of Helsinki,Helsinki,Finland
| | - M McGue
- Department of Psychology,University of Minnesota,Minneapolis, MN,USA
| | - J M Neiderhiser
- Department of Psychology,Penn State University,University Park,PA,USA
| | - N L Pedersen
- Department of Medical Epidemiology and Biostatistics,Karolinska Institutet,Stockholm,Sweden
| | - C A Reynolds
- Department of Psychology,University of California Riverside,Riverside, CA,USA
| | - M Gatz
- Department of Medical Epidemiology and Biostatistics,Karolinska Institutet,Stockholm,Sweden
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Abstract
Academic text books [corrected] are essential assets for disseminating knowledge about ADHD to future healthcare professionals. This study examined if they are balanced with regard to genetics. We selected and analyzed study books (N=43) used in (pre) master's programmes at 10 universities in the Netherlands. Because the mere behaviourally informed quantitative genetics give a much higher effect size of the genetic involvement in ADHD, it is important that text books [corrected] contrast these findings with molecular genetics' outcomes. The latter studies use real genetic data, and their low effect sizes expose the potential weaknesses of quantitative genetics, like underestimating the involvement of the environment. Only a quarter of books mention both effect sizes and contrast these findings, while another quarter does not discuss any effect size. Most importantly, however, roughly half of the books in our sample mention only the effect sizes from quantitative genetic studies without addressing the low explained variance of molecular genetic studies. This may confuse readers by suggesting that the weakly associated genes support the quite spectacular, but potentially flawed estimates of twin, family and adoption studies, while they actually contradict them.
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Affiliation(s)
- Sanne Te Meerman
- a Department of Special Needs Education and Child Care , University of Groningen , the Netherlands
| | - Laura Batstra
- a Department of Special Needs Education and Child Care , University of Groningen , the Netherlands
| | - Rink Hoekstra
- b Department of Educational Sciences, Learning & Instruction , University of Groningen , the Netherlands
| | - Hans Grietens
- a Department of Special Needs Education and Child Care , University of Groningen , the Netherlands
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