Study Objectives: Long and short sleep duration are associated with greater risk of developing post-traumatic stress disorder (PTSD); however, it is unknown how genetic and environmental influences impact this relationship. Thus, we investigated the association between sleep duration and PTSD symptoms using twin models. Methods: Data were obtained from 1,865 monozygotic and 758 dizygotic twin […]
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, […]
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 […]
Background: Individual sociodemographic and home neighborhood built environment (BE) factors influence the probability of engaging in health-enhancing levels of walking or moderate-to-vigorous physical activity (MVPA). Methods are needed to parsimoniously model the associations. Methods: Participants included 2392 adults drawn from a community-based twin registry living in the Seattle region. Objective BE measures from four domains […]
Background/objectives: The salience network (SN) comprises brain regions that evaluate cues in the external environment in light of internal signals. We examined the SN response to meal intake and potential genetic and acquired influences on SN function. Subjects/methods: Monozygotic (MZ; 40 pairs) and dizygotic (15 pairs) twins had body composition and plasma metabolic profile evaluated (glucose, insulin, […]
Approximately 12% of U.S. adults have type 2 diabetes (T2D). Diagnosed T2D is caused by a combination of genetic and environmental factors including age and lifestyle. In adults 45 years and older, the Discordant Twin (DISCOTWIN) consortium of twin registries from Europe and Australia showed a moderate-to-high contribution of genetic factors of T2D with a […]
Background: Nephrolithiasis is a complex phenotype influenced by both genetic and environmental factors. Previously we found a genetic component to stone disease using a sample of male twin pairs. We now report on the genetic contribution to stones in a sample of female and male twin pairs. Methods: We conducted a classic twin study of kidney stones […]
Background: Orolabial herpes simplex virus type 1 (HSV-1) infection has a wide spectrum of severity in immunocompetent persons. To study the role of viral genotype and host immunity, we characterized oral HSV-1 shedding rates and host cellular response, and genotyped viral strains, in monozygotic (MZ) and dizygotic (DZ) twins. Methods: A total of 29 MZ and 22 […]
Telfer S, Bigham JJ, Sudduth ASM. Identifying environmental risk factors for musculoskeletal disorders is challenging due to the number of potential confounders. Twins are of particular interest for researchers interested in studying these types of problems due to their inherent control for the influence of genetic factors. In twin studies, this population can allow environmental […]
Introduction: Age at menarche (AAM) is the point in development when the female starts her first menstrual period and is one of the first milestones in female reproductive life. A combination of genetic and environmental factors plays a role in the timing of female’s age at menarche. Material and methods: This study’s purpose was to […]
Background: It is unknown how familial factors influence the recovery from low back pain (LBP) and the maintenance activity behaviours. We aimed to investigate whether individual and within-family physical activity (PA) and sedentary behaviour influenced recovery from LBP, and maintenance of PA and sedentary behaviour in people with and without LBP. Methods: Longitudinal logistic regression analyses were […]
Background: There is considerable evidence that exposure to fine particulate matter (PM2.5) air pollution is associated with a variety of adverse health outcomes. However, true exposure-outcome associations are hampered by measurement issues, including compliance and exposure misclassification. Objective: This paper describes the use of the design-feedback iterative cycle to improve the design and usability of a new […]
Objective: This study aimed to determine whether a relationship was evident between gliosis in the mediobasal hypothalamus (MBH) and plasma testosterone concentrations in men. Methods: A total of 41 adult men (aged 18-50 years) from 23 twin pairs underwent fasting morning blood draw and brain magnetic resonance imaging. T2 relaxation time was used to quantify gliosis in […]
Major depression is a complex disorder with no single, direct causal mechanism. Morbidity has been linked to genetic processes, developmental history, and unique environmental exposures. Epigenetic mechanisms, especially DNA methylation, are also likely important factors in the pathogenesis of major depressive disorder (MDD). A community-based twin sample has many advantages for epigenetic studies, given the […]
Variation in healthy aging and lifespan is ascribed more to various non-genetic factors than to inherited genetic determinants, and a major goal in aging research is to reveal the epigenetic basis of aging. One approach to this goal is to find genomic sites or regions where DNA methylation correlates with biological age. Using health data […]
Objective: DNA methylation has been associated with both early life stress and depression. This study examined the combined association of DNA methylation at multiple CpG probes in five stress-related genes with depressive symptoms and tested whether these genes methylation mediated the association between childhood trauma and depression in two monozygotic (MZ) twin studies. Methods: The current analysis […]
Smart cities use information and communication technologies (ICT) to scale services include utilities and transportation to a growing population. In this article we discuss how smart city ICT can also improve healthcare effectiveness and lower healthcare cost for smart city residents. We survey current literature and introduce original research to offer an overview of how […]
Background: Body Mass Index (BMI), like most human phenotypes, is substantially heritable. However, BMI is not normally distributed; the skew appears to be structural, and increases as a function of age. Moreover, twin correlations for BMI commonly violate the assumptions of the most common variety of the classical twin model, with the MZ twin correlation greater […]
Social capital is associated with depression independently of individual-level risk factors. We used a sample of 1586 same-sex twin pairs to test the association between seven measures of social capital and two related measures of neighborhood characteristics with depressive symptoms accounting for uncontrolled selection factors (i.e., genetics and shared environment). All measures of cognitive social […]
Background: Depression is an important contributor to the global burden of disease. Besides several known individual-level factors that contribute to depression, there is a growing recognition that neighbourhood environment can also profoundly affect mental health. This study assessed associations between three neighbourhood constructs-socioeconomic deprivation, residential instability and income inequality-and depression among adult twin pairs. The twin […]
