The Children-of-Twins design was used to test whether associations between marital conflict frequency and conduct problems can be replicated within the children of discordant twin pairs. A sample of 2,051 children (age 14-39 years) of 1,045 twins was used to estimate the genetic and environmental influences on marital conflict and determine whether genetic or environmental selection processes u...

Between 4 to 6 million twins exist in the US today who offer scientists a valuable potential resource for conducting behavioral and biomedical research. However, unlike many other countries, there is no national system in the US for identifying twins and eliciting their participation in these important research programs. Therefore, the National Institute of Environmental Health Sciences (NIEHS)...

Monozygotic (MZ) twins form an important system for the study of biological plasticity in humans. While MZ twins are generally considered to be genetically identical, a number of studies have emerged that have demonstrated copy-number differences within a twin pair, particularly in those discordant for disease. The rate of autosomal copy-number variation (CNV) discordance within MZ twin pairs w...

The incidence of twin births in Accra and Kumasi, the two major cities in Ghana, was investigated. In Accra, data were collected from the Korle-Bu Teaching Hospital while data were collected and analyzed from the Komfo Anokye Teaching Hospital in Kumasi. Both hospitals are the leading teaching hospitals in Ghana. The data consisted mainly of single and twin births recorded in the hospitals over...

We applied multivariate models specifying genetic and environmental influences on adjectives describing each of the five personality domains specified in the Big Five Model of personality (BFM; Extraversion, Neuroticism, Agreeableness, Conscientiousness, and Openness). We selected the specific models to partition the observed covariance among the adjectives describing each domain into genetic a...

The classic twin study is sometimes described as "the perfect natural experiment" for the investigation of the aetiology of complex disease, but assumptions of the twin design need to be empirically tested if their results are to be considered unbiased and representative of singleton populations. In this study comparisons of disease and prevalence of lifestyle characteristics have been made bet...

Aim—To quantify the level of risk for stillbirth and infant death in singleton compared with twin pregnancies, using national data; to determine the independent eVects of zygosity, sex, and birthweight on these risks in twin pregnancies. Methods—A retrospective national study was carried out of all singleton and twin birth and death registrations in England and Wales 1982–91, according to sex a...

In order to evaluate the influence of the time interval on the second twin in twin deliveries, we have used more precise criteria than have been used in the literature to date. The following parameters of the twins were analyzed: normal CTG of the second twin recorded continuously during labor and pH value of the umbilical artery blood after delivery as well as clinical state according to the m...

O ur understanding of the causes of congenital heart defects has benefited tremendously from state-of-the-art genetic and epigenetic tools. The rapid progress is due in part to the development of novel, high-throughput, cost-effective sequencing technology—so-called next-generation sequenc-ing—that has made it possible to sequence the entire genome or all genes (whole exome sequencing). However...