Search results for "heritability"
showing 10 items of 141 documents
Genetic basis of trichome production in Arabidopsis lyrata.
2002
Leaf trichomes may protect plants against herbivorous insects, and may increase tolerance to drought and UV-radiation. The perennial herb Arabidopsis lyrata (Brassicaceae) is polymorphic for trichome production and occurs in a glabrous and trichome-producing form. In addition, there is quantitative variation in trichome density among trichome-producing plants. To examine the genetic basis of glabrousness, we conducted controlled crosses with plants originating from two natural populations in Sweden (one polymorphic for trichome-production, and one consisting of glabrous plants only). In addition, we estimated the heritability of trichome number from parent-offspring regressions for plants o…
Genetic and Environmental Effects on Telomere Length and Lung Function: A Twin Study.
2015
Background The purpose of the study was to estimate the heritability of leukocyte telomere length (LTL) and lung function and to examine whether LTL and lung function share genetic or environmental effects in common. Methods 386 monozygotic and dizygotic Finnish twin sisters (age 68.4±3.4 years) were included. Relative LTL was determined from peripheral blood DNA by qPCR. Lung function measures of FEV1, FVC, FEV1/FVC, and PEF were derived from spirometry. Genetic modeling was performed with MPlus statistical software. Results Univariate analysis revealed that in LTL, 62% (95% confidence interval 50-72) of the variance was explained by additive genetic and 38% (28-50) by unique environmental…
Genetic correlation between resistance to oxidative stress and reproductive life span in a bird species.
2010
Evolutionary theories propose that aging is the result of a trade-off between self-maintenance and reproduction, and oxidative stress may play a crucial role in such a trade-off. Phenotypic manipulations have revealed that a high investment in reproduction leads to a decline in the organism's resistance to oxidative stress, which could in turn accelerate aging. Here, by using quantitative genetic analyses as a tool to disentangle genetic effects from phenotypic variances, the relationship between resistance to oxidative stress at sexual maturity and two key reproductive life-history traits (i.e., number of breeding events during life and age at last reproduction) was analyzed in cross-foste…
Genetic variation in the primary sex ratio in populations of the intertidal copepod, Tigriopus californicus, is widespread on Vancouver Island.
2011
Hypothesis: Genetic variation for the primary sex ratio is widespread in a copepodwith polygenic sex determination. Cytoplasmic sex ratio distorters (e.g. Wolbachia andmicrosporidians) influence the primary sex ratio in this copepod. Organism: The intertidal copepod, Tigriopus californicus; six populations from VancouverIsland, British Columbia. Study site: Quantitative genetics experiment in the laboratory. PCR and antibioticsexperiment to test for the presence of cytoplasmic sex ratio distorters. Results: Genetic variation for the primary sex ratio was found in five of the six populationssurveyed. The primary sex ratio was paternally transmitted. There was no evidence thatWolbachia or mic…
Genetic and environmental contributions to serum ascorbic acid concentrations: the Stanislas Family Study.
2006
Although numerous environmental factors are documented to influence serum ascorbic concentrations, little is known about the genetic versus environmental contributions to variation of this trait. The aim of this study was to estimate family correlation and, additive genetic heritability and household effects in a variance component analysis for serum ascorbic acid concentrations. In a sample of ninety French families, information was obtained regarding serum ascorbic acid concentrations, usual dietary intake, lifestyle, and other related covariates. Spouse, parent –offspring and offspring –offspring significant correlation coefficients for serum ascorbic acid concentrations, adjusted for ag…
Defense against predators incurs high reproductive costs for the aposematic moth Arctia plantaginis
2020
Abstract To understand how variation in warning displays evolves and is maintained, we need to understand not only how perceivers of these traits select color and toxicity but also the sources of the genetic and phenotypic variation exposed to selection by them. We studied these aspects in the wood tiger moth Arctia plantaginis, which has two locally co-occurring male color morphs in Europe: yellow and white. When threatened, both morphs produce defensive secretions from their abdomen and from thoracic glands. Abdominal fluid has shown to be more important against invertebrate predators than avian predators, and the defensive secretion of the yellow morph is more effective against ants. Her…
Shared Genetic and Environmental Effects on Strength and Power in Older Female Twins
2005
Purpose: This study examined the relative contribution of genetic and environmental effects on maximal leg extensor power and also investigated whether leg extensor power and maximum voluntary isometric knee extensor strength share a genetic component. Methods: Muscle functions were measured as part of the Finnish Twin Study on Aging in 101 monozygotic (MZ) and 116 dizygotic (DZ) female twin pairs aged 63–76 yr. Leg extensor power was measured using the Nottingham Leg Extensor Power Rig and maximum voluntary isometric knee extensor strength using an adjustable dynamometer chair. The analyses were carried out using the maximum likelihood method in Mx-program on the raw data set. Results: A b…
Genetic association study of childhood aggression across raters, instruments, and age
2021
AbstractChildhood aggressive behavior (AGG) has a substantial heritability of around 50%. Here we present a genome-wide association meta-analysis (GWAMA) of childhood AGG, in which all phenotype measures across childhood ages from multiple assessors were included. We analyzed phenotype assessments for a total of 328 935 observations from 87 485 children aged between 1.5 and 18 years, while accounting for sample overlap. We also meta-analyzed within subsets of the data, i.e., within rater, instrument and age. SNP-heritability for the overall meta-analysis (AGGoverall) was 3.31% (SE = 0.0038). We found no genome-wide significant SNPs for AGGoverall. The gene-based analysis returned three sign…
A Genome-Wide Association Meta-Analysis of Attention-Deficit/Hyperactivity Disorder Symptoms in Population-Based Pediatric Cohorts
2016
OBJECTIVE: The aims of this study were to elucidate the influence of common genetic variants on childhood attention-deficit/hyperactivity disorder (ADHD) symptoms, to identify genetic variants that explain its high heritability, and to investigate the genetic overlap of ADHD symptom scores with ADHD diagnosis. METHOD: Within the EArly Genetics and Lifecourse Epidemiology (EAGLE) consortium, genome-wide single nucleotide polymorphisms (SNPs) and ADHD symptom scores were available for 17,666 children (<13 years of age) from nine population-based cohorts. SNP-based heritability was estimated in data from the three largest cohorts. Meta-analysis based on genome-wide association (GWA) analyses w…
Childhood aggression and the co-occurrence of behavioural and emotional problems: results across ages 3–16 years from multiple raters in six cohorts …
2018
Childhood aggression and its resulting consequences inflict a huge burden on affected children, their relatives, teachers, peers and society as a whole. Aggression during childhood rarely occurs in isolation and is correlated with other symptoms of childhood psychopathology. In this paper, we aim to describe and improve the understanding of the co-occurrence of aggression with other forms of childhood psychopathology. We focus on the co-occurrence of aggression and other childhood behavioural and emotional problems, including other externalising problems, attention problems and anxiety-depression. The data were brought together within the EU-ACTION (Aggression in Children: unravelling gene-…