Distribution and Heritability of Recurrent Ear Infections

1997 ◽  
Vol 106 (8) ◽  
pp. 624-632 ◽  
Author(s):  
Kari J. Kvaerner ◽  
Jennifer R. Harris ◽  
Kristian Tambs ◽  
Per Magnus
Keyword(s):  
Structural Equation ◽  
Genetic Factors ◽  
Age Of Onset ◽  
Population Based ◽  
Equation Modeling ◽  
Relative Contribution ◽  
Genes And Environment ◽  
Ear Infections ◽  
The Mean ◽  
Familial Environment

The distribution of recurrent ear infections was obtained from a population-based sample of 2,750 pairs of Norwegian twins born between 1967 and 1974. The lifetime prevalence of self-reported recurrent ear infections was 8.9%, with a significant predominance of female cases. The mean age of onset was 4.2 years, with a gradual decrease in occurrence from 2 to 7 years of age. Among monozygotic pairs, the rate of tetrachoric correlation between co-twins was almost identical in males (0.73, SE 0.08) and females (0.74, SE 0.06), but among the dizygotic pairs the correlation was clearly higher in males (0.53, SE 0.12) than in females (0.20, SE 0.12). The value in the unlike-sexed dizygotic twins (0.25, SE 0.05) was intermediate to that of the like-sexed male and female dizygotic pairs. The relative contribution of genes and environment to variability in the predisposition to develop otitis media was estimated by means of structural equation modeling. Variation in liability to ear infections was mainly explained by additive genetic and dominance factors in females, for whom heritability was estimated at 74%. The remaining 26% of the variation in liability was explained by individual environmental factors. In males, 45% of the variation could be accounted for by genetic factors, 29% by common familial environment, and the remaining 26% by individual environmental effects.

Genetic and Environmental Influences on Adiponectin, Leptin, and BMI Among Adolescents in Taiwan: A Multivariate Twin/Sibling Analysis

2008 ◽  
Vol 11 (5) ◽  
pp. 495-504 ◽  
Author(s):  
Pi-Hua Liu ◽  
Yi-Der Jiang ◽  
Wei J. Chen ◽  
Ching-Chung Chang ◽  
Tso-Ching Lee ◽  
...  
Keyword(s):  
Structural Equation ◽  
Monozygotic Twins ◽  
Equation Modeling ◽  
Shared Environment ◽  
Latent Factor ◽  
Sibling Pairs ◽  
Relative Contribution ◽  
Genes And Environment ◽  
Intraclass Correlations ◽  
Mz Twins

AbstractCirculating levels of leptin and adiponectin are closely associated with obesity. However, it is not known whether there are common shared genes or environment exerting influences on the levels of leptin, adiponectin, and BMI. We aimed to assess the relative contribution of genes and environment to adiponectin, leptin, and BMI individually as well as simultaneously to the three measures. Our subjects included a total of 228 twin/sibling pairs aged 12 to 18 (130 monozygotic twins, 68 dizygotic twins and 30 sibling pairs) were recruited from the middle schools. Multivariate analyses were applied to twin/sibling data using structural equation modeling. The results showed that intraclass correlations for adiponectin, leptin and BMI were higher in the MZ twins than those in the DZ/SP group. The relative contribution of genes to adiponectin (39%) was comparable to those of shared environment (40%). In contrast, leptin and BMI were influenced mostly by genes (74% and 89%, respectively). The multivariate genetic analyses showed that a latent factor underlying the three measures was identified, with BMI being equivalent to this latent factor. The BMI-dependent genetic factor explains only 15% and 34% of variation of adiponectin and leptin, respectively. These data indicate a differential contribution of genetic factors for the variation of adiponectin, leptin and BMI. More importantly, only a small portion of the genetic influences on adiponectin and leptin was attributed to BMI. Our findings provided more insight into the complex regulation of adiponectin and leptin in obesity.

A twin study of genetic and environmental influences on tobacco initiation, regular tobacco use and nicotine dependence

2004 ◽  
Vol 34 (7) ◽  
pp. 1251-1261 ◽  
Author(s):  
HERMINE H. MAES ◽  
PATRICK F. SULLIVAN ◽  
CYNTHIA M. BULIK ◽  
MICHAEL C. NEALE ◽  
CAROL A. PRESCOTT ◽  
...  
Keyword(s):  
Nicotine Dependence ◽  
Tobacco Use ◽  
Structural Equation ◽  
Genetic Factors ◽  
Smoking Behavior ◽  
Twin Studies ◽  
Population Based ◽  
Equation Modeling ◽  
Opposite Sex ◽  
Tobacco Initiation

Background. Numerous twin studies have reported significant genetic contributions to the variability of tobacco initiation (TI), while fewer studies have shown similar results for the persistence of smoking behavior, or nicotine dependence (ND). As the development of ND requires regular tobacco use (RTU) which in turn requires TI, a conditional approach is necessary.Method. We used structural equation modeling of multi-step conditional processes to examine the relationship between genetic and environmental risk factors for TI, RTU and ND. The tobacco variables were assessed by personal interview in female, male and opposite-sex twin pairs from the population-based Virginia Twin Registry.Results. The results suggested that the liabilities to TI, RTU and ND were correlated. Over 80% of the variance in liability to TI and RTU were shared, and a smaller proportion was shared between RTU and ND. The heritabilities were estimated at 75%, 80% and 60% respectively for TI, RTU and ND. The variance specific to liability to RTU was entirely accounted for by additive genetic factors. Only a modest part of the heritability in liability of ND was due to genetic factors specific to ND. Shared environmental factors were not significant. No sex differences were found for the sources of variation or causal paths, but prevalences were significantly greater in males versus females.Conclusions. This study showed significant overlap in the contribution of genetic factors to individual differences in TI, RTU and ND. Furthermore, there was evidence for significant additional genetic factors specific to RTU and ND.

scholarly journals Genetic Influences on Individual Differences in Exercise Behavior during Adolescence

2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Niels van der Aa ◽  
Eco J. C. De Geus ◽  
Toos C. E. M. van Beijsterveldt ◽  
Dorret I. Boomsma ◽  
Meike Bartels
Keyword(s):  
Structural Equation ◽  
Leisure Time ◽  
Genetic Factors ◽  
Threshold Model ◽  
Exercise Behavior ◽  
Equation Modeling ◽  
Substantial Part ◽  
Vigorous Exercise ◽  
Exercise Frequency ◽  
Age Cohorts

The aim of this study was to investigate the degree to which genetic and environmental influences affect variation in adolescent exercise behavior. Data on regular leisure time exercise activities were analyzed in 8,355 adolescent twins, from three-age cohorts (13-14, 15-16, and 17–19 years). Exercise behavior was assessed with survey items about type of regular leisure time exercise, frequency, and duration of the activities. Participants were classified as sedentary, regular exercisers, or vigorous exercisers. The prevalence of moderate exercise behavior declined from age 13 to 19 years with a parallel increase in prevalence of sedentary behavior, whereas the prevalence of vigorous exercise behavior remained constant across age cohorts. Variation in exercise behavior was analyzed with genetic structural equation modeling employing a liability threshold model. Variation was largely accounted for by genetic factors (72% to 85% of the variance was explained by genetic factors), whereas shared environmental factors only accounted for a substantial part of the variation in girls aged 13-14 years (46%). We hypothesize that genetic effects on exercise ability may explain the high heritability of exercise behavior in this phase of life.

Adolescent religiousness and its influence on substance use: preliminary findings from the Mid-Atlantic School Age Twin Study

Twin Research ◽  
1999 ◽  
Vol 2 (2) ◽  
pp. 156-168 ◽  
Author(s):  
Brian M D'Onofrio ◽  
Lenn Murrelle ◽  
Lindon J Eaves ◽  
Michael E McCullough ◽  
Jessica L Landis ◽  
...  
Keyword(s):  
Substance Use ◽  
Drug Use ◽  
Problem Behavior ◽  
Twin Study ◽  
Structural Equation ◽  
Population Based ◽  
Spiritual Practices ◽  
Equation Modeling ◽  
School Age ◽  
Attitudes And Practices

AbstractResearch has consistently shown that religiousness is associated with lower levels of alcohol and drug use, but little is known about the nature of adolescent religiousness or the mechanisms through which it influences problem behavior in this age group. This paper presents preliminary results from the Mid-Atlantic School Age Twin Study, a prospective, population-based study of 6–18-year-old twins and their mothers. Factor analysis of a scale developed to characterize adolescent religiousness, the Religious Attitudes and Practices Inventory (RAPI), revealed three factors: theism, religious/spiritual practices, and peer religiousness. Twin correlations and univariate behavior-genetic models for these factors and a measure of belief that drug use is sinful reveal in 357 twin pairs that common environmental factors significantly influence these traits, but a minor influence of genetic factors could not be discounted. Correlations between the multiple factors of adolescent religiousness and substance use, comorbid problem behavior, mood disorders, and selected risk factors for substance involvement are also presented. Structural equation modeling illustrates that specific religious beliefs about the sinfulness of drugs and level of peer religiousness mediate the relationship between theistic beliefs and religious/spiritual practices on substance use. Limitations and future analyses are discussed.

Efektifitas Sistem Informasi Manajemen Bagi Pengguna Internal (Studi Kasus Pada PT Bank Lampung)

2018 ◽  
Vol 2 (2) ◽  
Author(s):  
Alhibarsyah Alhibarsyah ◽  
Keyword(s):  
Information Technology ◽  
Structural Equation ◽  
Information Needs ◽  
Information Quality ◽  
Service Providers ◽  
Statistical Technique ◽  
Population Based ◽  
Equation Modeling ◽  
Observation Data ◽  
Technology System

Abstract To fulfill information needs that are relevant, fast, and accurate, the application of information technology, especially computer-based is inseparable from the role of the three basic components of a computer. The success model of the information technology system developed by DeLone & McLean quickly received a response. PT. Bank Lampung as one of the banking service providers in Lampung, is the object of research to determine how variables affect the level of Quality System, Information Quality, Service Quality, Use and Satisfaction and Use of Benefits, to determine the level of effectiveness in PT Bank Lampung's internal customer management information system. SEM (Structural Equation Modeling) is a multivariate statistical technique that is a combination of factor analysis and regression analysis (correlation), which aims to examine the relationship between variables in the model. To explain the overall relationship that exists between the variables in this study using AMOS software (Moment Structure Analysis). This shows that the sample variance-covariance matrix (observation data) I s the same as the estimated matrix of variance-covariance (population) based on the model built, it is expected that the results of this study KI significantly influence P, KI significantly affects KP, KS influences significant impact on P, significantly affecting KS KP, KL significantly affected P, KL significantly affected KP, P significantly affected KP, P significantly affected M, KP significantly affected M.

scholarly journals A Behavioral Model of Drivers’ Mean Speed Influenced by Weather Conditions, Road Geometry, and Driver Characteristics Using a Driving Simulator Study

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Mehdi Zolali ◽  
Babak Mirbaha ◽  
Maziyar Layegh ◽  
Hamid Reza Behnood
Keyword(s):  
Latent Variables ◽  
Latent Variable ◽  
Structural Equation ◽  
Driving Simulator ◽  
Weather Conditions ◽  
Geometric Design ◽  
Equation Modeling ◽  
Novice Drivers ◽  
Sight Distance ◽  
The Mean

Driving above the speed limit is one of the factors that significantly affect safety. Many studies examined the factors affecting the speed of vehicles in the simulated environment. The present study aimed to analyze drivers’ characteristics, time and weather conditions, and geometric features’ effect on mean speed in simulated conditions simultaneously. In this regard, the simulator experiment data of 70 drivers were collected in a two-lane rural highway at six different times, and weather scenarios and their socioeconomic characteristics were collected by a questionnaire. Structural equation modeling (SEM) was used to capture the complex relationships among related variables. Eleven variables were grouped into four latent variables in the structural model. Latent variables including “Novice Drivers,” “Experienced Drivers,” “Sight Distance,” and “Geometric Design” were defined and found significant on their mean speed. The results showed that “Novice Drivers” have a positive correlation with the mean speed. Meanwhile, “Experienced Drivers,” who drive 12% slower than the novice group, negatively affect the mean speed with a standard regression weight of −0.08. This relation means that young and novice drivers are more inclined to choose higher speeds. Among variables, the latent variable “Sight Distance” has the most significant effect on the mean speed. This model shows that foggy weather conditions strongly affect the speed selection behavior and reduce the mean speed by 40%. Nighttime also reduces mean speed due to poor visibility conditions. Furthermore, “Geometric design” as the latent variable indicates the presence of curves on the simulated road, and it can be concluded that the existence of a curve on the road encourages drivers to slow down, even young drivers. It is noteworthy that the parts of the simulated road with a horizontal curve act as a speed reduction tool for drivers.

Does the level of family dysfunction moderate the impact of genetic factors on the personality trait of neuroticism?

2003 ◽  
Vol 33 (5) ◽  
pp. 817-825 ◽  
Author(s):  
K. S. KENDLER ◽  
S. H. AGGEN ◽  
K. C. JACOBSON ◽  
M. C. NEALE
Keyword(s):  
Family Environment ◽  
Personality Trait ◽  
Structural Equation ◽  
Genetic Factors ◽  
False Negative ◽  
Population Based ◽  
Family Dysfunction ◽  
Twin Model ◽  
The Family ◽  
The Impact

Background. While the family environment can directly influence later risk for psychopathology, dysfunction in the family of origin may also moderate the impact of genetic factors on liability for psychiatric disorders. Can a similar pattern be seen for the personality trait of Neuroticism (N) – which is a risk factor for many psychiatric conditions?Method. Our sample of 957 complete female–female twin pairs from a population-based register had measures of self-reported N and multiple reporters (twin, co-twin, mother, father) for family dysfunction (FD). Statistical analysis was conducted by traditional regression analysis and a moderator structural equation twin model operationalized in the computer program Mx.Results. Dividing the sample into quartiles based on increasing levels of FD, the mean of N increased substantially while correlations of N in monozygotic (MZ) and dizygotic (DZ) twins were relatively constant. Regression analyses did not suggest greater twin resemblance for N with increasing levels of FD. The best-fit structural equation model was the standard un-moderated model in which the proportion of variance in N due to genetic (39%) and unique environmental effects (61%) remained constant across values of FD.Conclusions. Although a false-negative result due to limited power cannot be excluded, these analyses do not support the hypothesis that FD moderates the impact of genetic factors on levels of N.

scholarly journals Genetic and Environmental Influences on the Correlations between Traits of Metabolic Syndrome and CKD

2019 ◽  
Vol 14 (11) ◽  
pp. 1590-1596
Author(s):  
Xu Chen ◽  
Istiak Bhuiyan ◽  
Ralf Kuja-Halkola ◽  
Patrik K. E. Magnusson ◽  
Per Svensson
Keyword(s):  
Metabolic Syndrome ◽  
Abdominal Obesity ◽  
Structural Equation ◽  
Structural Equation Models ◽  
Environmental Influences ◽  
Population Based ◽  
European Ancestry ◽  
Cross Sectional ◽  
Environmental Correlations ◽  
Genes And Environment

Background and objectivesMetabolic syndrome is a cluster of risk factors associated with CKD. By studying the genetic and environmental influences on how traits of metabolic syndrome correlate with CKD, the understanding of the etiological relationships can be improved.Design, setting, participants, & measurementsFrom the population-based TwinGene project within the Swedish Twin Registry, 4721 complete twin pairs (9442 European ancestry participants) were included in this cross-sectional twin study. Metabolic syndrome-related continuous traits were measured, and the binary components as well as the status of metabolic syndrome were defined according to the National Cholesterol Education Program-Adult Treatment Panel III. The eGFR was calculated by cystatin C-based equations from the CKD epidemiology collaboration group, and CKD was defined by eGFR<60 ml/min per 1.73 m2. Genetic and environmental contributions to the correlations between traits of metabolic syndrome and CKD were estimated by using twin-based bivariate structural equation models.ResultsThe correlation between metabolic syndrome and eGFR-defined CKD was 0.16 (95% confidence interval [95% CI], 0.12 to 0.20), out of which 51% (95% CI, 12% to 90%) was explained by genes, whereas 15% (95% CI, 0% to 42%) and 34% (95% CI, 16% to 52%) was explained by the shared and nonshared environment, respectively. The genetic and environmental correlations between metabolic syndrome and CKD were 0.29 (95% CI, 0.07 to 0.51) and 0.27 (95% CI, 0.13 to 0.41), respectively. For the correlation between abdominal obesity and eGFR, 69% (95% CI, 10% to 100%) was explained by genes and 23% (95% CI, 5% to 41%) was explained by environment. The genetic correlation between abdominal obesity and eGFR was −0.30 (95% CI, −0.54 to −0.06), whereas the environmental correlation was −0.14 (95% CI, −0.22 to −0.06).ConclusionsBoth genes and environment contribute to the correlation between metabolic syndrome and eGFR-defined CKD. The genetic contribution is particularly important to the correlation between abdominal obesity and eGFR.

scholarly journals How Does Low Socioeconomic Status Increase Blood Lead Levelsin KoreanChildren?

2018 ◽  
Vol 15 (7) ◽  
pp. 1488 ◽  
Author(s):  
Eunjung Kim ◽  
Ho-jang Kwon ◽  
Mina Ha ◽  
Ji-Ae Lim ◽  
Myung Lim ◽  
...  
Keyword(s):  
Socioeconomic Status ◽  
Environmental Factors ◽  
Low Socioeconomic Status ◽  
Structural Equation ◽  
Blood Lead ◽  
Population Based ◽  
Equation Modeling ◽  
Cross Sectional ◽  
Korean Children ◽  
Low Socioeconomic

Although studies have shown that a low socioeconomic status (SES) is associated with high blood lead levels (BLLs) in children, the mechanism underlying this observation is not well known. To determine how SES influences BLLs via environmental factors in Korean children, we conducted a population-based cross-sectional study of 4744 children aged 5–13 years. Questionnaires on sociodemographic information, environmental factors, and food consumption were administered to the children’s parents. BLLs in the study subjects were measured.The complete set of hypothesized associations was assessed using regression analysis and structural equation modeling. SES was associated with high BLLs. The total effects of nutritional factors, lead in the air and total length of nearby roads, and agriculture on BLLs were −0.062 (p < 0.001), 0.068 (p = 0.005), and 0.038 (p = 0.035), respectively. The direct effects of playing outdoors and SES on BLLs were 0.113 (p < 0.001) and −0.111 (p < 0.001), respectively. Although playing outdoors had a greater direct effect on BLLs than did SES, the total effect of SES (standardized β = −0.132, p < 0.001) was greater than that of other sources owing to indirect effects (β = −0.020, p = 0.004). A low SES was a major risk factor for elevated BLLs via environmental factors.

Examination of the Contribution of Ruminative Thinking and Maladaptive Self-Beliefs to Social Anxiety

2016 ◽  
Vol 30 (4) ◽  
pp. 253-262 ◽  
Author(s):  
Kellie Kissell ◽  
Hayley Rodriguez ◽  
Lloyd Lucas ◽  
Brian Fisak
Keyword(s):  
Social Anxiety ◽  
Cognitive Processes ◽  
Structural Equation ◽  
Anxiety Symptoms ◽  
Equation Modeling ◽  
Event Processing ◽  
Anticipatory Anxiety ◽  
Relative Contribution ◽  
Anticipatory Processing ◽  
Nonclinical Sample

The purpose of this study was to examine the relative contribution of 3 components of the Clark and Wells (1995) model to social anxiety symptoms. In particular, based on theory and previous research, it was hypothesized that the association between post-event processing and social anxiety and between anticipatory anxiety and social anxiety would be mediated by maladaptive self-beliefs. To test this hypothesis, a large, nonclinical sample of young adults completed a measure of anticipatory processing, post-event processing, maladaptive self-beliefs, and social anxiety. Based on a structural equation modeling approach, full mediation was found between post-event processing and social anxiety, and partial mediation was found between anticipatory processing and social anxiety. Overall, the results contribute to the literature by elucidating cognitive processes that may lead to the development and maintenance of social anxiety symptoms.

Sign in / Sign up

Export Citation Format

Share Document