Twin and family studies establish the foundation for studying the genetic, environmental and cultural transmission effects for phenotypes. In this work, we make use of the well established statistical methods and theory for mixed models to assess cultural transmission in twin and family studies. Specifically, we address two critical yet poorly understood issues: the model identifiability in ass...

Correlations between relatives were determined for systolic and diastolic blood pressure. The correlations decrease as age differences between relatives increase in a Norwegian sample with 43,751 parent-offspring pairs, 19,140 pairs of siblings, and 169 pairs of twins. A simple biometric model specifying only age-specific genetic additive effects and environmental effects fitted well to correla...

The analysis of genetic and environmental contributions to preterm birth is not straightforward in family studies, as etiology could involve both maternal and fetal genes. Markov Chain Monte Carlo (MCMC) methods are presented as a flexible approach for defining user-specified covariance structures to handle multiple random effects and hierarchical dependencies inherent in children of twin (COT)...

Recent research has explored the relationships between family and cultural issues, claiming attention on the need to consider and evaluate cultural values and beliefs as useful factors to promote positive family adjustment and parenting outcomes (Cardoso and Thompson, 2010; Taylor et al., 2012). This paper explored self-perception of parental role, family maladjustment and cultural beliefs in a...

The challenge feminist scholarship posed to family studies has been largely met through the incorporation of research on gender dynamics within families and intersectional differences among them. Despite growing attention to gender as performance and power in more diverse families, the more difficult work of understanding the dynamics of change among institutions including the family and using ...

A biometrical genetical analysis of IgG, IgM, and IgA levels in 134 sets of twins is reported. High heritabilities, around .8, are found for all three immunoglobulin levels, and possible reasons for lower heritabilities found in family studies are discussed. There is evidence for genetical dominance tending to decrease IgM and IgA levels, but there is no evidence for the importance of family en...

OBJECTIVE Several components of event-related potentials--P50 suppression, P300 amplitude and latency, and mismatch negativity--have been proposed as potential endophenotypes for schizophrenia on the basis of family studies. The present study used a twin design to estimate the extent of genetic overlap between these indices and the liability to schizophrenia. METHOD The authors measured misma...

prevention efforts [1]. In this sample of Greenland Inuit where both HIV and undernutrition remain uncommon, the risk of developing TB was markedly higher in persons with co-existing diabetes than in persons without. The very high risk associated with diabetes suggests potential reduction in the Greenland TB incidence rates through incorporating diabetes control and prevention in TB prevention ...