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1.
Clin Epigenetics ; 11(1): 12, 2019 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-30660189

RESUMO

BACKGROUND: Epigenetic clocks may increase our understanding on human aging and how genetic and environmental factors regulate an individual aging process. One of the most promising clocks is Horvath's DNA methylation (DNAm) age. Age acceleration, i.e., discrepancy between DNAm age and chronological age, tells us whether the person is biologically young or old compared to his/her chronological age. Several environmental and lifestyle factors have been shown to affect life span. We investigated genetic and environmental predictors of DNAm age in young and older monozygotic (MZ) and dizygotic (DZ) twins with a focus on leisure time physical activity. RESULTS: Quantitative genetic modeling revealed that the relative contribution of non-shared environmental factors was larger among older compared with younger twin pairs [47% (95% CI 35, 63) vs. 26% (95% CI: 19, 35), p < 0.001]. Correspondingly, genetic variation accounted for less of the variance in older [53% (95% CI 37, 65)] compared with younger pairs [74% (95% CI 65, 82)]. We tested the hypothesis that leisure time physical activity is one of the non-shared environmental factors that affect epigenetic aging. A co-twin control analysis with older same-sex twin pairs (seven MZ and nine DZ pairs, mean age 60.4 years) who had persistent discordance in physical activity for 32 years according to reported/interviewed physical-activity data showed no differences among active and inactive co-twins, DNAm age being 60.7 vs. 61.8 years, respectively [between-group mean-difference: - 1.17 (95%CI - 3.43,1.10)]. Results from the younger cohort of twins supported findings that LTPA is not associated with DNAm age acceleration. CONCLUSIONS: In older subjects, a larger amount of variance in DNAm age acceleration was explained by non-shared environmental factors compared to young individuals. However, leisure time physical activity during adult years has at most a minor effect on DNAm age acceleration. This is consistent with recent findings that long-term leisure time physical activity in adulthood has little effect on mortality after controlling for genetic factors.


Assuntos
Metilação de DNA , Exercício , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Estudos de Coortes , Epigênese Genética , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Twin Res Hum Genet ; 22(1): 42-47, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30661511

RESUMO

There is a growing body of literature linking religious attendance to prosocial behavior (PB). The main purposes of the present study were to estimate genetic and environmental influences on the frequency of religious attendance (FRA) and to explore whether and how FRA moderates genetic and/or environmental influences on PB. As part of the Nigerian Twin and Sibling Study, 2860 (280 monozygotic male, 417 monozygotic female, 544 dizygotic male, 699 dizygotic female, and 920 opposite-sex dizygotic) twins (mean age = 14.2 years; SD = 1.7 years; age range = 12-18 years) completed a questionnaire regarding FRA and a PB scale. Similar to the findings from western twin samples, FRA showed substantial shared environmental influences of 74% (95% CI = 69%, 78%), with absence of genetic effects. The phenotypic correlation between FRA and PB was modest but positive and significant (r = .12; p < .01), suggesting that PB is higher among more frequent attenders than among less frequent attenders. The results of gene-environment (G × E) interaction model-fitting analysis revealed that FRA changed individual environmental experiences rather than genetic effects on PB such that while genetic variance was stable, non-shared environmental variance declined, leading the total phenotypic variance of PB to decrease with increasing levels of religious attendance.


Assuntos
Interação Gene-Ambiente , Modelos Genéticos , Religião , Comportamento Social , Inquéritos e Questionários , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Criança , Feminino , Humanos , Masculino , Nigéria
3.
Twin Res Hum Genet ; 22(1): 48-55, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30698127

RESUMO

This study uses novel approaches to examine genetic and environmental influences shared between childhood behavioral inhibition (BI) and symptoms of preadolescent anxiety disorders. Three hundred and fifty-two twin pairs aged 9-13 and their mothers completed questionnaires about BI and anxiety symptoms. Biometrical twin modeling, including a direction-of-causation design, investigated genetic and environmental risk factors shared between BI and social, generalized, panic and separation anxiety. Social anxiety shared the greatest proportion of genetic (20%) and environmental (16%) variance with BI with tentative evidence for causality. Etiological factors underlying BI explained little of the risk associated with the other anxiety domains. Findings further clarify etiologic pathways between BI and anxiety disorder domains in children.


Assuntos
Transtornos de Ansiedade/genética , Interação Gene-Ambiente , Inibição (Psicologia) , Inquéritos e Questionários , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Transtornos de Ansiedade/psicologia , Criança , Feminino , Humanos , Masculino , Gêmeos Dizigóticos/psicologia , Gêmeos Monozigóticos/psicologia
4.
Behav Genet ; 49(1): 1-10, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30536082

RESUMO

While a standard part of twin modeling, the magnitude of shared environment (c2) is rarely examined by comparing estimates obtained using other methods. To clarify these effects on familial resemblance, we estimated c2 for 20 diverse phenotypes in: (i) monozygotic and dizygotic twins, (ii) all step-siblings, and (iii) reared together and apart half-siblings, ascertained from the Swedish general population. The mean c2 estimates (± 95% CIs) differed across methods and were higher from twins (0.18; 0.13-0.23) than from the step (0.12; 0.09-0.14) and half-sibs (0.09; 0.06-0.13). c2 estimates correlated moderately across these three methods (ICC = + 0.28). When step-siblings from blended (each sib biologically related to one parent) and adoption-like families (one sib offspring of both parents and one of neither), were examined separately, resemblance was much lower in the latter. We need to clarify the range of environmental processes now considered together under the term "shared environment."


Assuntos
Interação Gene-Ambiente , Simulação por Computador , Meio Ambiente , Feminino , Humanos , Masculino , Modelos Genéticos , Pais , Fenótipo , Irmãos/etnologia , Meio Social , Suécia , Gêmeos/genética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
5.
J Drugs Dermatol ; 17(4): 380-382, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29601613

RESUMO

IMPORTANCE: Surveying identical twins allows us to qualitatively separate genetic and environmental factors that may contribute to acne severity. OBJECTIVE: To study a cohort of identical and fraternal twins to identify environmental factors that may influence acne severity. DESIGN, SETTING, PARTICIPANTS: A survey was administered to 139 identical and fraternal twin multiples (279 subjects) at the Annual Twins Day Festival in Twinsburg, Ohio on August 6-7, 2016. One set of triplets was included. MAIN OUTCOME(S) AND MEASURE(S): Acne incidence, severity, and triggers were analyzed using the N-1 Chi-squared test and paired, 2-tailed t test. RESULTS: The proportion of concordant pairs was significantly higher in identical (64%) vs fraternal (49%) twins (P=0.04). Acne was found to be associated with polycystic ovarian syndrome (PCOS; P=0.045), anxiety (P =0.014), and asthma (P=0.026). Identical twin pairs with acne had a higher BMI (P= 0.020) and exercised significantly less (P=0.001) than those without acne. Analyzing concordant twin pairs, the twin with more severe acne was more likely to report aggravation of acne with cosmetic product use (P=0.002) and sugar intake (P=0.048). CONCLUSIONS AND REVELANCE: This twin study further supports that there may be a genetic phenotypic link, though social and environmental factors may also have an influence in the disease process.

J Drugs Dermatol. 2018;17(4):380-382.

.


Assuntos
Acne Vulgar/epidemiologia , Acne Vulgar/genética , Congressos como Assunto , Inquéritos e Questionários , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Acne Vulgar/diagnóstico , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
6.
Behav Genet ; 48(2): 135-146, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29404830

RESUMO

This study used a theoretically-derived set of items of the Achenbach System of Empirically Based Assessment to develop the Achenbach Self-Control Scale (ASCS) for 7-16 year olds. Using a large dataset of over 20,000 children, who are enrolled in the Netherlands Twin Register, we demonstrated the psychometric properties of the ASCS for parent-, self- and teacher-report by examining internal and criterion validity, and inter-rater and test-retest reliability. We found associations between the ASCS and measures of well-being, educational achievement, and substance use. Next, we applied the classical twin design to estimate the genetic and environmental contributions to self-control. Genetic influences accounted for 64-75% of the variance in self-control based on parent- and teacher-report (age 7-12), and for 47-49% of the variance in self-control based on self-report (age 12-16), with the remaining variance accounted by non-shared environmental influences. In conclusion, we developed a validated and accessible self-control scale, and show that genetic influences explain a majority of the individual differences in self-control across youth aged 7-16 years.


Assuntos
Psicometria/métodos , Autocontrole/psicologia , Gêmeos/psicologia , Adolescente , Fatores Etários , Criança , Feminino , Interação Gene-Ambiente , Humanos , Individualidade , Masculino , Países Baixos , Pais , Inventário de Personalidade , Reprodutibilidade dos Testes , Autorrelato , Gêmeos/genética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
7.
BMJ Open ; 8(2): e017889, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29472256

RESUMO

INTRODUCTION: Non-communicable diseases (NCD) now represent the major burden of adverse health in most countries. It is clear that much of the risk of such conditions begins very early in life, potentially in utero. Given their complex aetiology, an understanding of the origins of NCD requires an in-depth analysis of the interplay between genetic variation and environment, preferably over time. For decades, twin studies have played a key role in understanding such traits. Their strength lies in the ability to disentangle genetic and environmental factors that contribute to a phenotype. This is done by comparing genetically identical monozygotic (MZ) with dizygotic twins, who share on average 50% of genetic variation, or by comparing MZ twins within a pair. This study aims to determine the relative contributions of genes and environment to early-onset intermediate phenotypes related to later adult onset disease (such as growth and neurodevelopment) and to identify specific biomarkers and time points for emergence of phenotypes from infancy, largely independent of underlying genetic factors. METHODS/DESIGN: The Chongqing Longitudinal Twin Study (LoTiS) will recruit 300 women pregnant with twins, enriched for MZ pregnancies, with follow-up to 3 years of age. Data collection will be undertaken at key time points in gestation (×3), at delivery and postnatally (×9). Maternal and infant biospecimens including blood, urine, hair, nails and buccal swabs along with measures such as fetal scans and body measurements will be collected. Additional information from questionnaires and medical records includes pregnancy, diet, sociodemographics, maternal stress, and infant growth and neurodevelopment. ETHICS AND DISSEMINATION: This study has been approved by the Ethics Committee of Chongqing Medical University (record no: 201530) and has been registered with the Chinese Clinical Trial Registry (registry no: ChiCTR-OOC-16008203). Results of the recruitment and all subsequent analyses will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ChiCTR-OOC-16008203; Results.


Assuntos
Meio Ambiente , Variação Genética , Projetos de Pesquisa , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Antropometria , Desenvolvimento Infantil , Pré-Escolar , China/epidemiologia , Feminino , Desenvolvimento Fetal , Humanos , Lactente , Estudos Longitudinais , Masculino , Doenças não Transmissíveis/epidemiologia , Gravidez , Fatores de Risco , Manejo de Espécimes , Ultrassonografia Pré-Natal
8.
Behav Genet ; 48(2): 109-124, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29427143

RESUMO

We investigated the etiological role of genetic and environmental influences for two milestones of tobacco and alcohol use: age of initiation, and speed of progression to dependence (latency). Study participants included 1352 monozygotic and 1422 dizygotic twins (mean age at assessment = 24.31). Earlier ages of initiation significantly increased the likelihood of developing dependence, but were associated with longer dependence latencies for tobacco and alcohol. Latencies to dependence were heritable traits for tobacco (a2 = 0.63) and alcohol (a2 = 0.64). Genetic influences contributing to early age of initiation were associated with faster latencies to dependence but sometimes were counteracted by environmental factors, the extent to which depended on substance and, sometimes, sex. Our findings may have important implications for public policy and add to the literature by characterizing the genetic and environmental contributions to the speed of progression to tobacco and alcohol dependence.


Assuntos
Alcoolismo/genética , Tabagismo/genética , Adolescente , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas/genética , Doenças em Gêmeos/genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Fatores de Risco , Fumar/genética , Transtornos Relacionados ao Uso de Substâncias/genética , Tabaco , Gêmeos/genética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
9.
Twin Res Hum Genet ; 21(1): 1-11, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29307321

RESUMO

Hundreds of penetrant risk loci have been identified across different neurodevelopmental disorders (NDDs), and these often involve rare (<1% frequency) copy number variations (CNVs), which can involve one or more genes. Monozygotic (MZ) twin pairs are long thought to share 100% of their genomic information. However, genetic differences in the form of postzygotic somatic variants have been reported recently both in typically developing (TD) and in clinically discordant MZ pairs. We sought to investigate the contribution of rare CNVs in 100 twin pairs enriched for NDD phenotypes with a particular focus on postzygotic CNVs in MZ pairs discordant for autism spectrum disorder (ASD) using the Illumina Infinium PsychArray. In our sample, no postzygotic de novo CNVs were found in 55 MZ twin pairs, including the 13 pairs discordant for ASD. We did detect a higher rate of CNVs overlapping genes involved in disorders of the nervous system, such as a rare deletion affecting HNRNPU, in MZ pairs discordant and concordant for ASD in comparison with TD pairs (p = .02). Our results are in concordance with earlier findings that postzygotic de novo CNV events are typically rare in genomic DNA derived from saliva or blood, and suggests that the discordance of NDDs in our sample of twins is not explained by discordant CNVs. Still, studies investigating postzygotic variation in MZ discordant twins using DNA from different tissues and single cells and higher resolution genomics are needed in the future.


Assuntos
Variações do Número de Cópias de DNA , Doenças em Gêmeos/genética , Transtornos do Neurodesenvolvimento/genética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Transtorno do Espectro Autista/genética , Criança , Feminino , Humanos , Masculino , Suécia , Adulto Jovem
10.
Twin Res Hum Genet ; 21(1): 24-32, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29369040

RESUMO

Until now, data have not been available to elucidate the genetic and environmental sources of comorbidity between all 10 DSM-IV personality disorders (PDs) and cocaine use. Our aim was to determine which PD traits are linked phenotypically and genetically to cocaine use. Cross-sectional data were obtained in a face-to-face interview between 1999 and 2004. Subjects were 1,419 twins (µage = 28.2 years, range = 19-36) from the Norwegian Institute of Public Health Twin Panel, with complete lifetime cocaine use and criteria for all 10 DSM-IV PDs. Stepwise multiple and Least Absolute Shrinkage and Selection Operator (LASSO) regressions were used to identify PDs related to cocaine use. Twin models were fitted to estimate genetic and environmental associations between the PD traits and cocaine use. In the multiple regression, antisocial (OR = 4.24, 95% CI [2.66, 6.86]) and borderline (OR = 2.19, 95% CI [1.35, 3.57]) PD traits were significant predictors of cocaine use. In the LASSO regression, antisocial, borderline, and histrionic were significant predictors of cocaine use. Antisocial and borderline PD traits each explained 72% and 25% of the total genetic risks in cocaine use, respectively. Genetic risks in histrionic PD were not significantly related to cocaine use. Importantly, after removing criteria referencing substance use, antisocial PD explained 65% of the total genetic variance in cocaine use, whereas borderline explained only 4%. Among PD traits, antisocial is the strongest correlate of cocaine use, for which the association is driven largely by common genetic risks.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/genética , Transtornos Relacionados ao Uso de Cocaína/psicologia , Transtornos da Personalidade/genética , Adulto , Transtorno da Personalidade Antissocial/genética , Estudos Transversais , Doenças em Gêmeos/genética , Feminino , Interação Gene-Ambiente , Humanos , Masculino , Análise Multivariada , Noruega , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
11.
J Obstet Gynaecol Res ; 44(3): 576-582, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29205694

RESUMO

A 39-year-old woman who became pregnant with twins after an intracytoplasmic sperm injection was referred at the ninth gestational week to determine chorionicity. Ultrasonographic examination showed a monochorionic diamniotic twin pregnancy. First trimester nuchal translucency measurements of the fetuses were 1.6 and 2.7 mm. A non-invasive prenatal test was performed and revealed low risk. One fetus appeared to be female and the other male at the 14th gestational week. Second trimester anatomic scanning results were otherwise normal for both fetuses. The newborns delivered at term appeared to be normal female and male babies phenotypically. At the fourth month, buccal cell analysis showed chimeric karyotypes, 46,XX[98]/46,XY[2] and 46,XY[98]/46,XX[2] in the female and male infant, respectively. The recognition of sex discordance despite monochorionicity may be a clue for the diagnosis of such rare cases of chimerism in dizygotic twins, most of which occur in pregnancies obtained by assisted reproductive technology.


Assuntos
Quimerismo , Córion/diagnóstico por imagem , Gravidez de Gêmeos , Injeções de Esperma Intracitoplásmicas , Gêmeos Dizigóticos , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Gêmeos Dizigóticos/genética , Ultrassonografia Pré-Natal
12.
Behav Genet ; 48(2): 147-154, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29264815

RESUMO

A previous meta-analysis (Van der Linden et al., Psychol Bull 143:36-52, 2017) showed that the General Factor of Personality (GFP) overlaps with ability as well as trait emotional intelligence (EI). The correlation between trait EI and the GFP was so high (ρ = 0.88) in that meta-analysis that these two may be considered virtually identical constructs. The present study builds on these findings by examining whether the strong phenotypic correlation between the GFP and trait EI has a genetic component. In a sample of monozygotic and dizygotic twins, the heritability estimates for the GFP and trait EI were 53 and 45%, respectively. Moreover, there was a strong genetic correlation of r = .90 between the GFP and trait EI. Additional analyses suggested that a substantial proportion of the genetic correlations reflects non-additive genetic effects (e.g., dominance and epistasis). These findings are discussed in light of evolutionary accounts of the GFP.


Assuntos
Inteligência Emocional/genética , Personalidade/genética , Adolescente , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Inteligência/genética , Masculino , Pessoa de Meia-Idade , Fenótipo , Inquéritos e Questionários , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
13.
Int J Cardiovasc Imaging ; 34(4): 531-541, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29022127

RESUMO

To disentangle genetic and environmental influences on the development of femoral plaques using a population of adult twins. To evaluate the potential role of shared genetic and environmental factors in the co-occurrence of femoral and carotid plaques. The sample included 566 twins belonging to 164 monozygotic (MZ) and 119 dizygotic (DZ) twin pairs, who underwent peripheral arterial assessment by B-mode ultrasound in different centers. The variance in femoral plaques onset was due to genetic factors and the remaining 50% was explained by common (15%) and unique (35%) environmental factors. Findings on sidedness and number of femoral plaques indicated that also these traits were mainly under genetic control. No effect of common environment was found on plaques composition, and variability of this trait was explained by genetics (64%) and unique environment (36%). Covariation between the liabilities to carotid and femoral plaques was mainly attributed to shared genes (77%), with the remaining 23% explained by individual-specific environmental factors shared by the two districts. Inter-individual differences in plaque onset as well as in their number, sidedness and composition are mainly genetic in origin. The results on the cooccurrence of carotid and femoral plaque underline the genetic role in atherogenesis.


Assuntos
Artérias Carótidas/patologia , Doenças das Artérias Carótidas/genética , Artéria Femoral/patologia , Interação Gene-Ambiente , Doença Arterial Periférica/genética , Placa Aterosclerótica , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto , Idoso , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/patologia , Espessura Intima-Media Carotídea , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Hungria , Itália , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/patologia , Fatores de Risco , Ultrassonografia Doppler em Cores , Adulto Jovem
14.
Behav Genet ; 48(1): 1-11, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29043520

RESUMO

For the participants in the Netherlands Twin Register (NTR) we constructed the extended pedigrees which specify all relations among nuclear and larger twin families in the register. A total of 253,015 subjects from 58,645 families were linked to each other, to the degree that we had information on the relations among participants. We describe the algorithm that was applied to construct the pedigrees. For > 30,000 adolescent and adult NTR participants data were available on harmonized neuroticism scores. We analyzed these data in the Mendel software package (Lange et al., Bioinformatics 29(12):1568-1570, 2013) to estimate the contributions of additive and non-additive genetic factors. In contrast to much of the earlier work based on twin data rather than on extended pedigrees, we could also estimate the contribution of shared household effects in the presence of non-additive genetic factors. The estimated broad-sense heritability of neuroticism was 47%, with almost equal contributions of additive and non-additive (dominance) genetic factors. A shared household effect explained 13% and unique environmental factors explained the remaining 40% of the variance in neuroticism.


Assuntos
Doenças em Gêmeos/genética , Neuroticismo/fisiologia , Gêmeos/genética , Família/psicologia , Feminino , Humanos , Masculino , Modelos Genéticos , Países Baixos/epidemiologia , Linhagem , Sistema de Registros , Meio Social , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
15.
Behav Genet ; 48(1): 44-54, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29098497

RESUMO

By taking advantage of the natural variation in genetic relatedness among identical (monozygotic: MZ) and fraternal (dizygotic: DZ) twins, twin studies are able to estimate genetic and environmental contributions to complex human behaviors. Recently concerns have been raised about the accuracy of twin studies in light of findings of genetic and epigenetic changes in twins. One of the concerns raised is that MZ twins are not 100% genetically and epigenetically similar because they show variations in their genomes and epigenomes leading to inaccurate estimates of heritability. This article presents findings from a simulation study that examined the degree of bias in estimates of heritability and environmentality when the genetic and epigenetic similarity of MZ twins differs from 1.00 and when the genetic and epigenetic similarity of DZ twins differs from 0.50. The findings suggest that in the standard biometric model when MZ or DZ twin similarity differs from 1.00 or 0.50, respectively, the variance that should be attributed to genetic influences is instead attributed to nonshared environmental influences, thus deflating the estimates of genetic influences and inflating the estimates of nonshared environmental influences. Although estimates of genetic and nonshared environmental influences from the standard biometric model were found to deviate from "true" values, the bias was usually smaller than 10% points indicating that the interpretations of findings from previous twin studies are mostly correct.


Assuntos
Biometria/métodos , Epigênese Genética/genética , Hereditariedade/genética , Viés , Simulação por Computador , Epigenômica/métodos , Feminino , Interação Gene-Ambiente , Variação Genética/genética , Humanos , Masculino , Sistema de Registros , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
16.
Acta Psychiatr Scand ; 137(1): 54-64, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29072781

RESUMO

OBJECTIVE: To investigate whether diagnostic data from structured interviews, primary care and specialist care registries on major depressive disorder (MDD), anxiety disorders (AD) and alcohol use disorder (AUD) identify the same individuals, yield comparable comorbidity estimates and reflect the same genetic influences. METHODS: Registry data from primary and specialist care were available for 11 727 twins and diagnostic interview data for 2271 of these. We used logistic regression analyses and biometric modelling to investigate the overlap between the data sources. RESULTS: Most individuals meeting diagnostic criteria at interview were not registered with a corresponding diagnosis. The rates of registration were higher for MDD (36% in primary care and 15% in specialist care) and AD (21% and 18%) than for AUD (3% and 7%). Comorbidity estimated as odds ratios, but not as polychoric correlations, was higher in the registries than in the interviews. Genetic influences on the disorders were highly correlated across data sources (median r = 0.81), bordering unity for MDD and AD. CONCLUSION: Prevalence and comorbidity estimates differ between registries and population-based assessment. Nevertheless, diagnoses from health registries reflect the same genetic influences as common mental disorders assessed in the general population, indicating generalizability of aetiological factors across data sources.


Assuntos
Alcoolismo/psicologia , Transtornos de Ansiedade/psicologia , Transtorno Depressivo Maior/psicologia , Sistema de Registros , Gêmeos/psicologia , Adolescente , Adulto , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , Alcoolismo/genética , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/genética , Comorbidade , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Feminino , Humanos , Entrevista Psicológica , Modelos Logísticos , Masculino , Noruega/epidemiologia , Razão de Chances , Gêmeos/genética , Gêmeos/estatística & dados numéricos , Gêmeos Dizigóticos/genética , Gêmeos Dizigóticos/psicologia , Gêmeos Dizigóticos/estatística & dados numéricos , Gêmeos Monozigóticos/genética , Gêmeos Monozigóticos/psicologia , Gêmeos Monozigóticos/estatística & dados numéricos , Adulto Jovem
17.
Behav Genet ; 48(1): 12-21, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28948422

RESUMO

Societal attitudes and norms to female smoking changed in Spain in the mid-twentieth century from a restrictive to a tolerant, and an even pro-smoking, posture, while social attitudes remained stable for males. We explored whether this difference in gender-related social norms influenced the heritability of two tobacco use measures: lifetime smoking and number of years smoking. We used a population-based sample of 2285 twins (mean age = 55.78; SD = 7.45; 58% females) whose adolescence began between the mid-1950s and the early 1980s. After modeling the effect of sex and year of birth on the variance components, we observed that the impact of the genetic and shared environmental factors varied differently by birth cohort between males and females. For females, shared environment explained a higher proportion of variance than the genetic factors in older cohorts. However, this situation was inverted in the younger female cohorts. In contrast, no birth cohort effect was observed for males, where the impact of the genetic and environmental factors remained constant throughout the study period. These results suggest that heritability is larger in a permissive social environment, whereas shared-environmental factors are more relevant in a society that is less tolerant to smoking.


Assuntos
Fumar Cigarros/genética , Interação Gene-Ambiente , Hereditariedade/genética , Meio Social , Adulto , Idoso , Atitude , Doenças em Gêmeos/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Mudança Social , Espanha , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
18.
Age Ageing ; 47(1): 119-125, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28985290

RESUMO

Introduction: frailty is an increased vulnerability to adverse health outcomes, across multiple physiological systems, with both environmental and genetic drivers. The two most commonly used measures are Rockwood's frailty index (FI) and Fried's frailty phenotype (FP). Material and methods: the present study included 3626 individuals from the TwinsUK Adult Twin Registry. We used the classical twin model to determine whether FI and FP share the same latent aetiological factors. We also investigated the relationship between frailty and chronic widespread musculoskeletal pain (CWP), another holistic age-related condition with significant clinical impact. Results: FP and FI shared underlying genetic and environmental aetiology. CWP was associated with both frailty measures, and health deficits appeared to mediate the relationship between phenotypic frailty and pain. Latent genetic factors underpinning CWP were shared with frailty. While frailty was increased in the twins reporting pain, co-twin regression analysis indicated that the relationship between CWP and frailty is reduced after accounting for shared genetic and environmental factors. Conclusions: both measures of frailty tap the same root causes, thus this work helps unify frailty research. We confirmed a strong association between CWP and frailty, and showed a large and significant shared genetic aetiology of both phenomena. Our findings argue against pain being a significant causative factor in the development of frailty, favouring common causation. This study highlights the need to manage CWP in frail individuals and undertake a Comprehensive Geriatric Assessment in individuals presenting with CWP. Finally, the search for genetic factors underpinning CWP and frailty could be aided by integrating measures of pain and frailty.


Assuntos
Dor Crônica/genética , Fragilidade/genética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Dor Crônica/diagnóstico , Feminino , Idoso Fragilizado , Fragilidade/diagnóstico , Interação Gene-Ambiente , Predisposição Genética para Doença , Avaliação Geriátrica/métodos , Hereditariedade , Humanos , Pessoa de Meia-Idade , Medição da Dor , Fenótipo , Sistema de Registros , Fatores de Risco , Reino Unido , Adulto Jovem
19.
Twin Res Hum Genet ; 20(6): 541-549, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29110752

RESUMO

Acne vulgaris is a skin disease with a multifactorial and complex pathology. While several twin studies have estimated that acne has a heritability of up to 80%, the genomic elements responsible for the origin and pathology of acne are still undiscovered. Here we performed a twin-based structural equation model, using available data on acne severity for an Australian sample of 4,491 twins and their siblings aged from 10 to 24. This study extends by a factor of 3 an earlier analysis of the genetic factors of acne. Acne severity was rated by nurses on a 4-point scale (1 = absent to 4 = severe) on up to three body sites (face, back, chest) and on up to three occasions (age 12, 14, and 16). The phenotype that we analyzed was the most severe rating at any site or age. The polychoric correlation for monozygotic twins was higher (r MZ = 0.86, 95% CI [0.81, 0.90]) than for dizygotic twins (r DZ = 0.42, 95% CI [0.35, 0.47]). A model that includes additive genetic effects and unique environmental effects was the most parsimonious model to explain the genetic variance of acne severity, and the estimated heritability was 0.85 (95% CI [0.82, 0.87]). We then conducted a genome-wide analysis including an additional 271 siblings - for a total of 4,762 individuals. A genome-wide association study (GWAS) scan did not detect loci associated with the severity of acne at the threshold of 5E-08 but suggestive association was found for three SNPs: rs10515088 locus 5q13.1 (p = 3.9E-07), rs12738078 locus 1p35.5 (p = 6.7E-07), and rs117943429 locus 18q21.2 (p = 9.1E-07). The 5q13.1 locus is close to PIK3R1, a gene that has a potential regulatory effect on sebocyte differentiation.


Assuntos
Acne Vulgar/genética , Doenças em Gêmeos/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Acne Vulgar/epidemiologia , Acne Vulgar/fisiopatologia , Adolescente , Adulto , Austrália/epidemiologia , Criança , Doenças em Gêmeos/epidemiologia , Doenças em Gêmeos/fisiopatologia , Feminino , Humanos , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Sistema de Registros , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
20.
Curr Biol ; 27(22): 3554-3560.e3, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29129535

RESUMO

Where one looks within their environment constrains one's visual experiences, directly affects cognitive, emotional, and social processing [1-4], influences learning opportunities [5], and ultimately shapes one's developmental path. While there is a high degree of similarity across individuals with regard to which features of a scene are fixated [6-8], large individual differences are also present, especially in disorders of development [9-13], and clarifying the origins of these differences is essential to understand the processes by which individuals develop within the complex environments in which they exist and interact. Toward this end, a recent paper [14] found that "social visual engagement"-namely, gaze to eyes and mouths of faces-is strongly influenced by genetic factors. However, whether genetic factors influence gaze to complex visual scenes more broadly, impacting how both social and non-social scene content are fixated, as well as general visual exploration strategies, has yet to be determined. Using a behavioral genetic approach and eye tracking data from a large sample of 11-year-old human twins (233 same-sex twin pairs; 51% monozygotic, 49% dizygotic), we demonstrate that genetic factors do indeed contribute strongly to eye movement patterns, influencing both one's general tendency for visual exploration of scene content, as well as the precise moment-to-moment spatiotemporal pattern of fixations during viewing of complex social and non-social scenes alike. This study adds to a now growing set of results that together illustrate how genetics may broadly influence the process by which individuals actively shape and create their own visual experiences.


Assuntos
Movimentos Oculares/genética , Visão Ocular/genética , Atenção , Criança , Olho , Movimentos Oculares/fisiologia , Face , Feminino , Fixação Ocular/genética , Humanos , Masculino , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Percepção Visual/genética
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