Modeling Genetic and Environmental Factors to Increase Heritability and Ease the Identification of Candidate Genes for Birth Weight: A Twin Study

AbstractThere is a commonly observed association between chronic disease and psychological distress, but many potential factors could confound this association. This study investigated the association using a powerful twin study design that can control for unmeasured confounders that are shared between twins, including genetic and environmental factors. We used twin-paired cross-sectional data from the Adult Health and Lifestyle Questionnaire collected by Twins Research Australia from 2014 to 2017. Linear regression models fitted using maximum likelihood estimations (MLE) were used to test the association between self-reported chronic disease status and psychological distress, measured by the Kessler Psychological Distress Scale (K6). When comparing between twin pairs, having any chronic disease was associated with a 1.29 increase in K6 (95% CI: 0.91, 1.66; p < .001). When comparing twins within a pair, having any chronic disease was associated with a 0.36 increase in K6 (95% CI: 0.002, 0.71; p = .049). This within-pair estimate is of most interest as comparing twins within a pair naturally controls for shared factors such as genes, age and shared lived experiences. Whereas the between-pair estimate does not. The weaker effect found within pairs tells us that genetic and environmental factors shared between twins confounds the relationship between chronic disease and psychological distress. This suggests that associations found in unrelated samples may show exaggerated estimates.

Download Full-text

Exploring the association between genetic and environmental factors and molar incisor hypomineralization: evidence from a twin study

International Journal of Paediatric Dentistry ◽

10.1111/ipd.12327 ◽

2017 ◽

Vol 28 (2) ◽

pp. 198-206 ◽

Cited By ~ 22

Author(s):

Rafael José Pio Barbosa Teixeira ◽

Natália Silva Andrade ◽

Lisanca Carvalho Cavalcante Queiroz ◽

Fausto Medeiros Mendes ◽

Marcoeli Silva Moura ◽

...

Keyword(s):

Environmental Factors ◽

Twin Study ◽

Molar Incisor Hypomineralization ◽

Genetic And Environmental Factors

Download Full-text

Genetic and Environmental Influences on Smoking Behavior across Adolescence and Young Adulthood in the Virginia Twin Study of Adolescent Behavioral Development and the Transitions to Substance Abuse Follow-Up

Twin Research and Human Genetics ◽

10.1017/thg.2014.78 ◽

2015 ◽

Vol 18 (1) ◽

pp. 43-51 ◽

Cited By ~ 11

Author(s):

Elizabeth K. Do ◽

Elizabeth C. Prom-Wormley ◽

Lindon J. Eaves ◽

Judy L. Silberg ◽

Donna R. Miles ◽

...

Keyword(s):

Environmental Factors ◽

Young Adulthood ◽

Twin Study ◽

Smoking Behavior ◽

Smoking Initiation ◽

Study Results ◽

Adolescence And Young Adulthood ◽

Genetic And Environmental Factors ◽

The Relationship

Little is known regarding the underlying relationship between smoking initiation and current quantity smoked during adolescence into young adulthood. It is possible that the influences of genetic and environmental factors on this relationship vary across sex and age. To investigate this further, the current study applied a common causal contingency model to data from a Virginia-based twin study to determine: (1) if the same genetic and environmental factors are contributing to smoking initiation and current quantity smoked; (2) whether the magnitude of genetic and environmental factor contributions are the same across adolescence and young adulthood; and (3) if qualitative and quantitative differences in the sources of variance between males and females exist. Study results found no qualitative or quantitative sex differences in the relationship between smoking initiation and current quantity smoked, though relative contributions of genetic and environmental factors changed across adolescence and young adulthood. More specifically, smoking initiation and current quantity smoked remain separate constructs until young adulthood, when liabilities are correlated. Smoking initiation is explained by genetic, shared, and unique environmental factors in early adolescence and by genetic and unique environmental factors in young adulthood; while current quantity smoked is explained by shared environmental and unique environmental factors until young adulthood, when genetic and unique environmental factors play a larger role.

Download Full-text

Corneal fluorescence in relation to genetic and environmental factors: a twin study

Acta Ophthalmologica Scandinavica ◽

10.1034/j.1600-0420.2003.00089.x ◽

2003 ◽

Vol 81 (5) ◽

pp. 508-513 ◽

Cited By ~ 4

Author(s):

Line Kessel ◽

Jesper Leth Hougaard ◽

Kirsten Ohm Kyvik ◽

Birgit Sander ◽

Thorkild I. A. Sørensen ◽

...

Keyword(s):

Environmental Factors ◽

Twin Study ◽

Genetic And Environmental Factors

Download Full-text

Contribution of genetic and environmental factors to variation in body compartments - a twin study in adults

Anthropologischer Anzeiger ◽

10.1127/anthranz/62/2004/51 ◽

2004 ◽

Vol 62 (1) ◽

pp. 51-60 ◽

Cited By ~ 11

Author(s):

Dorin Hanisch ◽

Manuela Dittmar ◽

Thomas Höhler ◽

Kurt W. Alt

Keyword(s):

Environmental Factors ◽

Twin Study ◽

Body Compartments ◽

Genetic And Environmental Factors

Download Full-text

Muscle Dissatisfaction and Muscle-Enhancing Substance Use: A Population-Based Twin Study in Young Adult Men

Twin Research and Human Genetics ◽

10.1375/twin.9.3.431 ◽

2006 ◽

Vol 9 (3) ◽

pp. 431-437 ◽

Cited By ~ 3

Author(s):

Anu Raevuori ◽

Anna Keski-Rahkonen ◽

Richard J. Rose ◽

Aila Rissanen ◽

Jaakko Kaprio

Keyword(s):

Substance Use ◽

Environmental Factors ◽

Twin Study ◽

Genetic Factors ◽

Population Based ◽

Tetrachoric Correlation ◽

Polychoric Correlation ◽

Adult Men ◽

Genetic And Environmental Factors ◽

Best Fit

AbstractIn the population-based FinnTwin16 study, proportions of genetic and environmental factors contributing to muscle dissatisfaction and muscle-enhancing substance use were assessed in 319 pairs of twin brothers: 141 monozygotic (MZ) and 178 dizygotic (DZ) pairs. In addition there were 86 twin individuals from pairs in which only one co-twin responded. Of all respondents, 30% experienced high muscle dissatisfaction. The corresponding proportion of muscle-enhancing substance use was 10%. The subjects were similar in age (23.8 years, 95% confidence interval [CI] 23.76–23.84), body mass index (23.7, 95% CI 23.5–23.9), and waist circumference (84.5 cm, 95% CI 83.7–85.2), independent of their muscle dissatisfaction or muscle-enhancing substance use status and independent of their zygosity. The MZ polychoric correlation for muscle dissatisfaction was .39 (95% CI .17–.58) and .27 for DZ pairs (95% CI .07–.46). The MZ tetrachoric correlation for muscle-enhancing substance use was .65 (95% CI .28–.87) and .56 for DZ pairs (95% CI .26–.78). The AE model, where additive genetic factors (A) accounted for 42% (95% CI .23–.59) and unique environmental factors (E) 58% (95% CI .41–.77) of the liability, provided the best fit for muscle dissatisfaction. The CE model, where common environmental factors (C) accounted for 60% (95% CI .37–.77) and unique environmental factors (E) 40% (95% CI .23–.63) of the liability, provided the best fit for muscle-enhancing substance use. Both genetic and unique (nonfamilial) environmental factors are involved in muscle dissatisfaction in the population. Nongenetic factors (both familial and non-familial) appear to best explain the use of muscle-enhancing substances.

Download Full-text

Exploring Genetic and Environmental Influences on Miscarriage Rates: A Twin Study

Twin Research and Human Genetics ◽

10.1375/twin.13.2.201 ◽

2010 ◽

Vol 13 (2) ◽

pp. 201-206 ◽

Cited By ~ 3

Author(s):

Andrea V. Burri ◽

Lynn Cherkas ◽

Timothy D. Spector

Keyword(s):

Environmental Factors ◽

Twin Study ◽

Variance Components ◽

Model Fitting ◽

Genetic Influence ◽

Shared Environment ◽

Pair Correlations ◽

Relative Contribution ◽

Genetic And Environmental Factors ◽

Common Variable

AbstractMiscarriage is the most common type of pregnancy loss, occurring in up to 15% of clinically recognized pregnancies. Our understanding of the etiology is still limited but is believed to be multifactorial, including endocrine and anatomical abnormalities, immunologic, genetic and lifestyle factors. The aim of this study was to explore whether genetic variability in miscarriage is under any genetic influence. 3234 MZ and DZ female twins completed postal self-completion questionnaires on pregnancies. Rates were adjusted for total number of pregnancies. The relative contribution of genetic and environmental factors to variation in miscarriage was assessed using twin intra-pair correlations and quantified using a variance components model fitting approach. We found 22.7% of our twins reporting having suffered at least one miscarriage. Current age, age at first pregnancy and higher number of pregnancies all had a significant influence on reported miscarriage. The concordance of miscarriage was similar in identical and non-identical twins, 26% and 27%, respectively. Shared environment and predominantly random error and unique environment rather than genetic factors best explained the total variation of miscarriage. To our knowledge, this is the first large twin study exploring heritability of miscarriage which unlike the vast majority of common variable traits, shows no significant genetic influence. In the absence of clear environmental factors, these results suggest the influence of random factors.

Download Full-text

Genetic and environmental factors in the determination of general cognitive abilities: a twin study

ASIAN JOURNAL OF HOME SCIENCE ◽

10.15740/has/ajhs/15.2/171-176 ◽

2020 ◽

Vol 15 (2) ◽

pp. 171-176

Author(s):

Annu ◽

Bimla Dhanda

Keyword(s):

Environmental Factors ◽

Cognitive Abilities ◽

Twin Study ◽

Monozygotic Twins ◽

Heritability Estimate ◽

Intelligence Scale ◽

Wide Range ◽

Heritability Estimates ◽

Genetic And Environmental Factors

The present investigation of twin study elucidated the contribution of genetic and environment to a wide range of general cognitive abilities. To conduct twin study 100 pairs of twins from two districts, namely: Bhiwani (n = 90) and Hisar (n = 110) of Haryana State, genetic and environmental influences were assessed in twin study design. The cognitive abilities of twins were measured using the Wechsler Intelligence Scale for Children (WISC-R). Home Observation for Measurement of the Environment (HOME) Inventory was taken to examine the home environment of twins. Heritability estimate was used to analyze the genes contributing to shape the cognitive abilities of twins. The result of heritability estimates revealed that the heritability estimates of general cognitive abilities namely: information (62%), similarities (57%), vocabulary (60%) and comprehension (55%) in Bhiwani district and in Hisar district, the heritability estimates were 58 per cent, 55 per cent, 56 per cent and 51 per cent for information, similarities, vocabulary and comprehension general cognitive abilities, respectively. The findings clearly elucidated that the general cognitive abilities were more influenced by genetic background than the environmental factors. The paternal involvement and physical environment were strongly associated with general cognitive abilities of twins. The monozygotic twins were more correlated in their general cognitive abilities than the dizygotic twins.

Download Full-text