95 research outputs found
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Microwave-dried or air-dried? Consumers' stated preferences and attitudes for organic dried strawberries. A multi-country investigation in Europe
Non-thermal food processing technologies are becoming more important in the organic food sector because, beyond preserving the organic feature, they could offer organic products with additional benefits in terms of enhanced nutritional content and healthiness as well as better sensory properties that could satisfy the more complex demands of organic consumers. Berries have a well-known health benefits and show increasing market shares in European markets while dehydration can increase the food convenience in terms of extended shelf-life. This study investigates for the first time organic consumers' stated preferences, attitudes and individual differences for a non-thermal organic processing technology. Specifically, we investigated consumers' preferences for organic dried strawberries varying in drying technology used, such as the most conventional (i.e. thermal) air drying and the most innovative (i.e. non-thermal) microwave drying, origin, price levels, and nutrient contents in three European countries: Norway, Romania and Turkey. Data from a total of 614 consumers were collected through an online choice experiment. Results show that on average consumers prefer organic dried strawberries produced with air drying technology that have national origin, with natural nutrient content and at low price, but country and individual differences are identified. Consumers who showed least rejection for microwave dried products are young, mostly from Norway and have higher positive attitudes towards new food technologies. Consumers who showed most rejection for microwave dried products are older, mostly from Turkey and have higher positive attitudes for organic, natural and ecological products. Organic producers who adopt microwave drying might better inform consumers about the characteristics, the process and highlight the nutritional benefits of such technology. Finally, this research informs policy makers about the need to define and regulate more clearly microwave drying as an organic technology, as well as to regulate labelling to ensure that consumers are not misled and correctly informed about the new technology
A DNA Methylation Biomarker of Alcohol Consumption
The lack of reliable measures of alcohol intake is a major obstacle to the diagnosis and treatment of alcohol-related diseases. Epigenetic modifications such as DNA methylation may provide novel biomarkers of alcohol use. To examine this possibility, we performed an epigenome-wide association study of methylation of cytosine-phosphate-guanine dinucleotide (CpG) sites in relation to alcohol intake in 13 population-based cohorts (ntotal=13 317; 54% women; mean age across cohorts 42–76 years) using whole blood (9643 European and 2423 African ancestries) or monocyte-derived DNA (588 European, 263 African and 400 Hispanic ancestry) samples. We performed meta-analysis and variable selection in whole-blood samples of people of European ancestry (n=6926) and identified 144 CpGs that provided substantial discrimination (area under the curve=0.90–0.99) for current heavy alcohol intake (≥ 42 g per day in men and ≥ 28 g per day in women) in four replication cohorts. The ancestry-stratified meta-analysis in whole blood identified 328 (9643 European ancestry samples) and 165 (2423 African ancestry samples) alcohol-related CpGs at Bonferroni-adjusted P \u3c 1 × 10−7. Analysis of the monocyte-derived DNA (n = 1251) identified 62 alcohol-related CpGs at P \u3c 1 × 10-7. In whole-blood samples of people of European ancestry, we detected differential methylation in two neurotransmitter receptor genes, the γ-Aminobutyric acid-A receptor delta and γ-aminobutyric acid B receptor subunit 1; their differential methylation was associated with expression levels of a number of genes involved in immune function. In conclusion, we have identified a robust alcohol-related DNA methylation signature and shown the potential utility of DNA methylation as a clinically useful diagnostic test to detect current heavy alcohol consumption
Largest GWAS of PTSD (N=20 070) yields genetic overlap with schizophrenia and sex differences in heritability
The Psychiatric Genomics Consortium-Posttraumatic Stress Disorder group (PGC-
PTSD) combined genome-wide case–control molecular genetic data across 11
multiethnic studies to quantify PTSD heritability, to examine potential shared
genetic risk with schizophrenia, bipolar disorder, and major depressive
disorder and to identify risk loci for PTSD. Examining 20 730 individuals, we
report a molecular genetics-based heritability estimate (h2SNP) for European-
American females of 29% that is similar to h2SNP for schizophrenia and is
substantially higher than h2SNP in European-American males (estimate not
distinguishable from zero). We found strong evidence of overlapping genetic
risk between PTSD and schizophrenia along with more modest evidence of overlap
with bipolar and major depressive disorder. No single-nucleotide polymorphisms
(SNPs) exceeded genome-wide significance in the transethnic (overall) meta-
analysis and we do not replicate previously reported associations. Still, SNP-
level summary statistics made available here afford the best-available
molecular genetic index of PTSD—for both European- and African-American
individuals—and can be used in polygenic risk prediction and genetic
correlation studies of diverse phenotypes. Publication of summary statistics
for ∼10 000 African Americans contributes to the broader goal of increased
ancestral diversity in genomic data resources. In sum, the results demonstrate
genetic influences on the development of PTSD, identify shared genetic risk
between PTSD and other psychiatric disorders and highlight the importance of
multiethnic/racial samples. As has been the case with schizophrenia and other
complex genetic disorders, larger sample sizes are needed to identify specific
risk loci
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International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.
The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations
A DNA methylation biomarker of alcohol consumption.
The lack of reliable measures of alcohol intake is a major obstacle to the diagnosis and treatment of alcohol-related diseases. Epigenetic modifications such as DNA methylation may provide novel biomarkers of alcohol use. To examine this possibility, we performed an epigenome-wide association study of methylation of cytosine-phosphate-guanine dinucleotide (CpG) sites in relation to alcohol intake in 13 population-based cohorts (ntotal=13 317; 54% women; mean age across cohorts 42-76 years) using whole blood (9643 European and 2423 African ancestries) or monocyte-derived DNA (588 European, 263 African and 400 Hispanic ancestry) samples. We performed meta-analysis and variable selection in whole-blood samples of people of European ancestry (n=6926) and identified 144 CpGs that provided substantial discrimination (area under the curve=0.90-0.99) for current heavy alcohol intake (⩾42 g per day in men and ⩾28 g per day in women) in four replication cohorts. The ancestry-stratified meta-analysis in whole blood identified 328 (9643 European ancestry samples) and 165 (2423 African ancestry samples) alcohol-related CpGs at Bonferroni-adjusted P<1 × 10-7. Analysis of the monocyte-derived DNA (n=1251) identified 62 alcohol-related CpGs at P<1 × 10-7. In whole-blood samples of people of European ancestry, we detected differential methylation in two neurotransmitter receptor genes, the γ-Aminobutyric acid-A receptor delta and γ-aminobutyric acid B receptor subunit 1; their differential methylation was associated with expression levels of a number of genes involved in immune function. In conclusion, we have identified a robust alcohol-related DNA methylation signature and shown the potential utility of DNA methylation as a clinically useful diagnostic test to detect current heavy alcohol consumption.Medical Research Council (Grant IDs: MC_UU_12015/1, MC_UU_12015/2), Wellcome Trust. Detailed acknowledgements are included in the Supplementary Information that accompanies the paper on the Molecular Psychiatry website
Enhancing discovery of genetic variants for posttraumatic stress disorder through integration of quantitative phenotypes and trauma exposure information
Background Posttraumatic stress disorder (PTSD) is heritable and a potential consequence of exposure to traumatic stress. Evidence suggests that a quantitative approach to PTSD phenotype measurement and incorporation of lifetime trauma exposure (LTE) information could enhance the discovery power of PTSD genome-wide association studies (GWASs). Methods A GWAS on PTSD symptoms was performed in 51 cohorts followed by a fixed-effects meta-analysis (N = 182,199 European ancestry participants). A GWAS of LTE burden was performed in the UK Biobank cohort (N = 132,988). Genetic correlations were evaluated with linkage disequilibrium score regression. Multivariate analysis was performed using Multi-Trait Analysis of GWAS. Functional mapping and annotation of leading loci was performed with FUMA. Replication was evaluated using the Million Veteran Program GWAS of PTSD total symptoms. Results GWASs of PTSD symptoms and LTE burden identified 5 and 6 independent genome-wide significant loci, respectively. There was a 72% genetic correlation between PTSD and LTE. PTSD and LTE showed largely similar patterns of genetic correlation with other traits, albeit with some distinctions. Adjusting PTSD for LTE reduced PTSD heritability by 31%. Multivariate analysis of PTSD and LTE increased the effective sample size of the PTSD GWAS by 20% and identified 4 additional loci. Four of these 9 PTSD loci were independently replicated in the Million Veteran Program. Conclusions Through using a quantitative trait measure of PTSD, we identified novel risk loci not previously identified using prior case-control analyses. PTSD and LTE have a high genetic overlap that can be leveraged to increase discovery power through multivariate methods
A putative causal relationship between genetically determined female body shape and posttraumatic stress disorder
Background: The nature and underlying mechanisms of the observed increased vulnerability to posttraumatic stress disorder (PTSD) in women are unclear. Methods: We investigated the genetic overlap of PTSD with anthropometric traits and reproductive behaviors and functions in women. The analysis was conducted using female-specific summary statistics from large genome-wide association studies (GWAS) and a cohort of 3577 European American women (966 PTSD cases and 2611 trauma-exposed controls). We applied a high-resolution polygenic score approach and Mendelian randomization analysis to investigate genetic correlations and causal relationships. Results: We observed an inverse association of PTSD with genetically determined anthropometric traits related to body shape, independent of body mass index (BMI). The top association was related to BMI-adjusted waist circumference (WCadj; R = -0.079, P < 0.001, Q = 0.011). We estimated a relative decrease of 64.6% (95% confidence interval = 27.5-82.7) in the risk of PTSD per 1-SD increase in WCadj. MR-Egger regression intercept analysis showed no evidence of pleiotropic effects in this association (Ppleiotropy = 0.979). We also observed associations of genetically determined WCadj with age at first sexual intercourse and number of sexual partners (P = 0.013 and P < 0.001, respectively). Conclusions: There is a putative causal relationship between genetically determined female body shape and PTSD, which could be mediated by evolutionary mechanisms involved in human sexual behaviors
Largest GWAS of PTSD (N=20 070) yields genetic overlap with schizophrenia and sex differences in heritability.
The Psychiatric Genomics Consortium-Posttraumatic Stress Disorder group (PGC-PTSD) combined genome-wide case-control molecular genetic data across 11 multiethnic studies to quantify PTSD heritability, to examine potential shared genetic risk with schizophrenia, bipolar disorder, and major depressive disorder and to identify risk loci for PTSD. Examining 20 730 individuals, we report a molecular genetics-based heritability estimate (
Largest GWAS of PTSD (N=20 070) yields genetic overlap with schizophrenia and sex differences in heritability
The Psychiatric Genomics Consortium-Posttraumatic Stress Disorder group (PGC-PTSD) combined genome-wide case-control molecular genetic data across 11 multiethnic studies to quantify PTSD heritability, to examine potential shared genetic risk with schizophrenia, bipolar disorder, and major depressive disorder and to identify risk loci for PTSD. Examining 20 730 individuals, we report a molecular genetics-based heritability estimate (h 2 SNP) for European-American females of 29% that is similar to h 2 SNP for schizophrenia and is substantially higher than h 2 SNP in European-American males (estimate not distinguishable from zero). We found strong evidence of overlapping genetic risk between PTSD and schizophrenia along with more modest evidence of overlap with bipolar and major depressive disorder. No single-nucleotide polymorphisms (SNPs) exceeded genome-wide significance in the transethnic (overall) meta-analysis and we do not replicate previously reported associations. Still, SNP-level summary statistics made available here afford the best-available molecular genetic index of PTSD - for both European- and African-American individuals - and can be used in polygenic risk prediction and genetic correlation studies of diverse phenotypes. Publication of summary statistics for 1/410 000 African Americans contributes to the broader goal of increased ancestral diversity in genomic data resources. In sum, the results demonstrate genetic influences on the development of PTSD, identify shared genetic risk between PTSD and other psychiatric disorders and highlight the importance of multiethnic/racial samples. As has been the case with schizophrenia and other complex genetic disorders, larger sample sizes are needed to identify specific risk loci
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