Search results for "twin"
showing 10 items of 435 documents
Association of maternal prenatal smoking GFI1-locus and cardio-metabolic phenotypes in 18,212 adults
2018
Background: DNA methylation at the GFI1-locus has been repeatedly associated with exposure to smoking from the foetal period onwards. We explored whether DNA methylation may be a mechanism that links exposure to maternal prenatal smoking with offspring's adult cardio-metabolic health.Methods: We meta-analysed the association between DNA methylation at GFI1-locus with maternal prenatal smoking, adult own smoking, and cardio-metabolic phenotypes in 22 population-based studies from Europe, Australia, and USA (n= 18,212). DNA methylation at the GFI1-locus was measured in whole-blood. Multivariable regression models were fitted to examine its association with exposure to prenatal and own adult s…
Heritability of Spherical Equivalent
2010
Purpose To examine the heritability of spherical equivalent (SE) in older women. Design Population-based twin study. Participants Ninety monozygotic (MZ) and 86 dizygotic (DZ) female twin pairs aged 63 to 76 years who were born from 1924 through 1937. Methods Ocular refraction was measured using an autorefractor and controlled by the subjective method. The contributions of genetic and environmental factors to individual differences in SE were estimated by applying an independent pathway model to twin data. Main Outcome Measures Contribution of genetic and environmental effects to the variation in SE. Results Mean SE of the study population was 1.68 (standard deviation, ±1.82) with no differ…
Intronic L1 insertion and F268S, novel mutations in RPS6KA3 (RSK2) causing Coffin-Lowry syndrome
2003
Two novel mutations of the ribosomal S6 kinase 2 gene (also known as RSK2) have been identified in two unrelated patients with Coffin–Lowry syndrome. The first mutation consists of a de novo insertion of a 5′-truncated LINE-1 element at position −8 of intron 3, which leads to a skipping of exon 4, leading to a shift of the reading frame and a premature stop codon. The L1 fragment (2800 bp) showed a rearrangement with a small deletion, a partial inversion of the ORF 2, flanked by short direct repeats which duplicate the acceptor splice site. However, cDNA analysis of the patient shows that both sites are apparently not functional. The second family showed the nucleotide change 803T>C in exon…
Genetics in restless legs syndrome
2004
Several studies on Restless leas syndrome (RLS) have suggested a substantial genetic contribution in the etiology of this sleep disorder. Clinical surveys of idiopathic RLS patients have shown that up to 60% report a positive family history. Investigations of single families with RLS have suggested an autosomal dominant mode of inheritance with variable expressivity, and some families show possible anticipation. At present, only one twin study is available, showing a high concordance rate (83.3%) between identical twins. Despite several reports suggesting a genetic contribution to the etiology of idiopathic RLS, few molecular genetic studies have been carried out attempting to identify gene…
Percorsi di geografia tra cultura, società e turismo
2011
Il volume propone alcuni studi che mettono in relazione la Geografia con la cultura, la società e il turismo. La scoperta di nuovi orizzonti d’indagine e il tentativo di nuovi metodi di analisi sono alla base dell’evoluzione a cui è sottoposta da pochi decenni la disciplina, di cui il volume è una delle possibili rappresentazioni. La logica dei saggi consente al lettore di disporre di ampia flessibilità nell’individuazione di appositi percorsi di studio o di ricerca.
Weierstraß’s Approximation Theorem (1885) and his 1886 lecture course revisited
2015
The paper provides new insight into the origins of Weierstras’s 1886 lecture course on the foundations of function theory and of the mimeographed lecture notes connected to this course which were published by the author in German in 1988. A short overview of the content of the lecture course is given; the central role that Weierstras’s famous approximation theorem of 1885 played in it is emphasized. The paper uses archival material recently discovered at the Institut Mittag-Leffler in Djursholm.
Genetic influences on adult body mass index followed over 29 years and their effects on late-life mobility: a study of twin sisters.
2009
Background: The rise in body mass index (BMI) during adulthood increases the risk for metabolic disorders, functional limitations and disability in old age. This twin study examined prospectively whether genetic and environmental influences on women’s BMI also account for mobility 29 years later. Methods: The sample consisted of 103 monozygotic and 114 dizygotic pairs of twin sisters reared together. Body mass index was initially evaluated in 1975, when the women were aged 42.6±3.4 years, and was followed-up in 1981, 1990, 2001 and 2004. Mobility was evaluated using the standardised 6-minute walking test in 2001, when the women were aged 68.6±3.2 years, and followed-up 3 years later. An inv…
A longitudinal study on genetic and environmental influences on leisure time physical activity in the Finnish Twin Cohort.
2010
The purpose of this study was to examine changes in the contribution of genetic and environmental influences to leisure time physical activity among male and female twins over a 6-year follow-up. At baseline the sample comprised 4,280 monozygotic and 9,276 dizygotic twin individuals, and at follow-up 4,383 monozygotic and 9,439 dizygotic twin individuals. Participants were aged 18–54 years at baseline. Genetic modeling results showed that genetic influences on leisure time physical activity declined from baseline (44%) to follow-up (34%). Most of the genetic influences identified at baseline were present at followup (rg= 0.72). Specific environmental influences increased from baseline (56%)…
Effects of 32-year leisure time physical activity discordance in twin pairs on health (TWINACTIVE study): aims, design and results for physical fitne…
2009
AbstractThe physically active lifestyle is associated with low future morbidity and mortality, but the causality between physical activity and health is not always clear. As some inherited biological characteristics and childhood experiences may cause selection bias in observational studies, we sought to take them into account by identifying 16 twin pairs (7 MZ, 9 DZ, mean age 60 years) discordant for leisure time physical activity habits for thirty years. We conducted detailed health-related examinations among these twin pairs. Our main aims were to study the effects of physical activity and genes on fitness and body composition, with special reference to body fat compartments, metabolic s…
Effect of physical activity on health in twins: a 30-yr longitudinal study.
2010
Purpose: The aim of this study was to investigate whether persistent leisure-time physical activity, adjusted for genetic liability and childhood experiences, protects against chronic diseases, early signs of disability, and loss of life satisfaction. Methods: From 5663 healthy adult twin pairs, we identified 146 pairs who were discordant for both intensity and volume of leisure physical activity in 1975 and 1981. Of them, both members of 95 pairs were alive and participated in our follow-up study in 2005 when chronic diseases (such as diabetes, cardiovascular disease, and osteoarthritis), life satisfaction, and disability were assessed by a structured telephone interview. The mean age of t…