ABSTRACT
Carotid intima media thickness (cIMT) is a biomarker of subclinical atherosclerosis and a predictor of future cardiovascular events. Identifying associations between gene expression levels and cIMT may provide insight to atherosclerosis etiology. Here, we use two approaches to identify associations between mRNA levels and cIMT: differential gene expression analysis in whole blood and S-PrediXcan. We used microarrays to measure genome-wide whole blood mRNA levels of 5647 European individuals from four studies. We examined the association of mRNA levels with cIMT adjusted for various potential confounders. Significant associations were tested for replication in three studies totaling 3943 participants. Next, we applied S-PrediXcan to summary statistics from a cIMT genome-wide association study (GWAS) of 71 128 individuals to estimate the association between genetically determined mRNA levels and cIMT and replicated these analyses using S-PrediXcan on an independent GWAS on cIMT that included 22 179 individuals from the UK Biobank. mRNA levels of TNFAIP3, CEBPD and METRNL were inversely associated with cIMT, but these associations were not significant in the replication analysis. S-PrediXcan identified associations between cIMT and genetically determined mRNA levels for 36 genes, of which six were significant in the replication analysis, including TLN2, which had not been previously reported for cIMT. There was weak correlation between our results using differential gene expression analysis and S-PrediXcan. Differential expression analysis and S-PrediXcan represent complementary approaches for the discovery of associations between phenotypes and gene expression. Using these approaches, we prioritize TNFAIP3, CEBPD, METRNL and TLN2 as new candidate genes whose differential expression might modulate cIMT.
Subject(s)
Atherosclerosis , Carotid Intima-Media Thickness , Gene Expression , Genome-Wide Association Study , Humans , Risk FactorsABSTRACT
BACKGROUND: Pain is the clinical hallmark of sickle cell disease (SCD) leading to hospitalization, psychological sequelae and a decreased health-related quality of life. The aim of this systematic literature review is to evaluate the efficacy of non-pharmacological interventions in reducing sickle cell related pain in children with SCD. METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, a comprehensive literature search up until October 2022 was performed to identify studies that investigated the efficacy of non-pharmacological interventions on (1) pain frequency and/or intensity, and (2) analgesic and health service use in children with SCD until the age of 21. Both randomized controlled trials (RCTs) and quasi-experimental designed (QED) studies were considered for inclusion. RESULTS: Ten articles (five RCTs and five QED studies) with 422 participants were included. They investigated cognitive behavioural therapy (CBT) (n = 5), biofeedback (n = 2), massage (n = 1), virtual reality (n = 1) and yoga (n = 1). The majority of the interventions were psychological (n = 7) and were performed in the outpatient clinic (n = 6). CBT and biofeedback significantly reduced frequency and/or intensity of SCD-related pain in outpatient settings, while virtual reality and yoga significantly reduced pain in inpatient settings. Biofeedback also significantly reduced analgesic use. None of the included articles reported reduced health service use. CONCLUSION: Non-pharmacological interventions may be effective in reducing pain in paediatric patients with SCD. However, due to the heterogeneity of the included studies a quantitative analysis could not be performed. Awaiting further supporting evidence, healthcare providers should consider implementing these interventions as valuable part of a comprehensive pain management strategy plan.
Subject(s)
Anemia, Sickle Cell , Cognitive Behavioral Therapy , Child , Humans , Pain Management , Pain/drug therapy , Analgesics/therapeutic use , Anemia, Sickle Cell/complicationsABSTRACT
Inhibitor development is a major complication of treatment with factor VIII concentrates in nonsevere haemophilia A. It has been suggested that plasma-derived factor VIII (FVIII) concentrates elicit fewer inhibitors than recombinant FVIII concentrates, but studies in severe haemophilia A patients have shown conflicting results. We designed a case-control study to investigate the clinical and genetic risk factors for inhibitor development in nonsevere haemophilia A patients. We investigated whether the type of FVIII concentrate was associated with inhibitor development in nonsevere haemophilia A patients. This nested case-control study includes 75 inhibitor patients and 223 controls, from a source population of the INSIGHT study, including all nonsevere haemophilia A patients (FVIII:C 2-40%) that were treated with FVIII concentrates in 33 European and one Australian centre. Cases and controls were matched for date of birth and cumulative number of exposure days (CED) to FVIII concentrate. A conditional logistic regression model was used to calculate unadjusted and adjusted odds ratios. No increased risk for inhibitor development was found for any type of FVIII concentrate; either when comparing recombinant FVIII concentrates to plasma-derived FVIII concentrates (adjusted odds ratio 0·96, 95% confidence interval (CI) 0·36-2·52) or for specific types of FVIII concentrates.
Subject(s)
Blood Coagulation Factor Inhibitors/blood , Factor VIII , Hemophilia A , Adolescent , Adult , Child , Child, Preschool , Factor VIII/administration & dosage , Factor VIII/antagonists & inhibitors , Factor VIII/metabolism , Hemophilia A/blood , Hemophilia A/drug therapy , Humans , Male , Middle Aged , Retrospective Studies , Risk FactorsABSTRACT
INTRODUCTION AND AIM: Knowledge on patterns of beliefs about the illness (illness cognitions) can provide insight into individual differences in adjustment to haemophilia. The current study aimed to identify (a) which sociodemographic and disease characteristics were associated with illness cognitions and (b) which illness cognitions were associated with health-related quality of life (HRQOL) in young adult men with haemophilia, besides sociodemographic and disease characteristics. METHODS: Young adult men (18-30 years) with haemophilia in the Netherlands participated in an online multicentre cross-sectional study. Participants completed the Pediatric Quality of Life Inventory Young Adult version (PedsQL_YA). Potential sociodemographic determinants were assessed with the Course of Life Questionnaire (CoLQ) and illness cognitions with the Illness Cognition Questionnaire (ICQ). Multiple linear regression analyses were performed to assess potential determinants of illness cognitions and HRQOL. RESULTS: Seventy young adult men with haemophilia (mean age 24.7 years, SD 3.5) participated. Born outside the Netherlands (ß -0.24) and >1 bleed past 6 months (ß -0.32) were associated with less acceptance of the disease. More acceptance was associated with better HRQOL in all domains: ß 0.23-0.39. More helplessness was associated with worse total (ß -0.30) and physical (ß -0.42) HRQOL. Disease benefits, sociodemographic and disease characteristics were not associated with HRQOL. CONCLUSION: Illness cognitions are associated with HRQOL in young adult men with haemophilia. Early recognition and identification of illness cognitions are important to facilitate support and psychosocial treatment to optimize young adults' well-being. Extra attention is needed for young adult men with frequent bleeds because they are at risk of lowered levels of acceptance of the disease.
Subject(s)
Cognition/physiology , Hemophilia A/psychology , Quality of Life/psychology , Adolescent , Adult , Humans , Male , Young AdultABSTRACT
Microbial presence and regrowth in drinking water distribution systems (DWDSs) is routinely monitored to assess the biological stability of drinking water without a residual disinfectant, but the conventional microbiological culture methods currently used target only a very small fraction of the complete DWDS microbiome. Here, we sequenced 16S rRNA gene amplicons to elucidate the attached and suspended prokaryotic community dynamics within three nonchlorinated DWDSs with variable regrowth conditions distributing similarly treated surface water from the same source. One rural location, with less regrowth related issues, differed most strikingly from the other two urban locations by the exclusive presence of Pseudonocardia (Actinobacteria) in the biofilm and the absence of Limnobacter (Betaproteobacteriales) in the water and loose deposits during summer. There was a dominant seasonal effect on the drinking water microbiomes at all three locations. For one urban location, it was established that the most significant changes in the microbial community composition on a spatial scale occurred shortly after freshly treated water entered the DWDS. However, summerly regrowth of Limnobacter, one of the dominant genera in the distributed drinking water, already occurred in the clean water reservoir at the treatment plant before further distribution. The highlighted bacterial lineages within these highly diverse DWDS communities might be important new indicators for undesirable regrowth conditions affecting the final drinking water quality.
Subject(s)
Drinking Water , Microbiota , Water Purification , Bacteria/genetics , Biofilms , RNA, Ribosomal, 16S/genetics , Water Microbiology , Water Quality , Water SupplyABSTRACT
Epigenetic modifications, including DNA methylation, represent a potential mechanism for environmental impacts on human disease. Maternal smoking in pregnancy remains an important public health problem that impacts child health in a myriad of ways and has potential lifelong consequences. The mechanisms are largely unknown, but epigenetics most likely plays a role. We formed the Pregnancy And Childhood Epigenetics (PACE) consortium and meta-analyzed, across 13 cohorts (n = 6,685), the association between maternal smoking in pregnancy and newborn blood DNA methylation at over 450,000 CpG sites (CpGs) by using the Illumina 450K BeadChip. Over 6,000 CpGs were differentially methylated in relation to maternal smoking at genome-wide statistical significance (false discovery rate, 5%), including 2,965 CpGs corresponding to 2,017 genes not previously related to smoking and methylation in either newborns or adults. Several genes are relevant to diseases that can be caused by maternal smoking (e.g., orofacial clefts and asthma) or adult smoking (e.g., certain cancers). A number of differentially methylated CpGs were associated with gene expression. We observed enrichment in pathways and processes critical to development. In older children (5 cohorts, n = 3,187), 100% of CpGs gave at least nominal levels of significance, far more than expected by chance (p value < 2.2 × 10(-16)). Results were robust to different normalization methods used across studies and cell type adjustment. In this large scale meta-analysis of methylation data, we identified numerous loci involved in response to maternal smoking in pregnancy with persistence into later childhood and provide insights into mechanisms underlying effects of this important exposure.
Subject(s)
DNA Methylation , Epigenesis, Genetic , Smoking/adverse effects , Asthma/etiology , Asthma/genetics , Child , Child, Preschool , Chromosome Mapping , Cleft Lip/etiology , Cleft Lip/genetics , Cleft Palate/etiology , Cleft Palate/genetics , Female , Genetic Association Studies , Humans , Infant , Infant, Newborn , Pregnancy , White People/geneticsABSTRACT
INTRODUCTION: Accurate assessment of joint health in persons with haemophilia is crucial. Several haemophilia-specific measurement tools are available, but an overview of the measurement properties is lacking. AIM: To provide an overview of the measurement properties of haemophilia-specific measurement tools to assess clinical joint health. METHODS: MEDLINE and EMBASE were searched for reports on reliability, validity or responsiveness of the World Federation of Haemophilia Orthopedic Joint Score (WFH), Colorado Physical Examination Score (CPE), joint examination score by Petrini (PJS) and Hemophilia Joint Health Score (HJHS). Methodological quality of the studies was assessed using an adapted COSMIN checklist. RESULTS: The search yielded 2905 unique hits, and 98 papers were included. The methodological quality of the included studies was limited. The HJHS was studied most extensively, which yielded limited evidence for good internal consistency and structural validity, moderate evidence for hypothesis testing in adults and conflicting evidence for hypothesis testing in children. Reliability, measurement error and responsiveness were rated unknown due to low COSMIN scores. For the CPE and PJS, we found limited to moderate evidence for good responsiveness and conflicting evidence for hypothesis testing. CONCLUSION: Only patchy evidence is available on the quality of measurement properties of all haemophilia-specific joint health scores. Although significant gaps in the evidence for all instruments remain, measurement properties of the HJHS were most extensively studied and show no drawbacks for use in clinical practice. This review forms the basis for further research aimed at the assessment of measurement properties of measurement tools to assess joint health.
Subject(s)
Hemophilia A/pathology , Joint Diseases/pathology , Joints/physiopathology , Databases, Factual , Hemophilia A/complications , Humans , Joint Diseases/etiology , Physical Examination/methods , Quality of Life , Severity of Illness IndexABSTRACT
INTRODUCTION AND AIM: Suboptimal health-related quality of life and lowered employment rates found in a previous study in young adults (YA) with congenital coagulation disorders (CCD) in the Netherlands underline the need for more insight into professional functioning of YA with CCD and into determinants of professional functioning. METHODS: Young adults (18-30 years) with CCD participated in a cross-sectional study. Professional functioning was assessed with the Work Productivity and Activity Impairment questionnaire (WPAI). Potential determinants were assessed with the Course of Life Questionnaire (CoLQ), Pediatric Quality of Life Inventory Young Adult version (PedsQL_YA), Illness Cognition Questionnaire (ICQ) and Haemophilia Activities List (HAL). Logistic regression analyses were performed in the complete sample of YA with CCD, and in YA men with haemophilia separately, to examine determinants of WPAI outcomes. RESULTS: Ninety-four YA (77 men; mean age 24.1 years, SD 3.5 and 17 women; mean age 24.5 years, SD 3.8) with CCD (74% haemophilia A/B) participated. 74.5% of YA were paid employed for on average 30 hours per week. Of these, more than a quarter reported work impairment. Older age and a non-severe type of haemophilia (in the sample of YA men with haemophilia) were associated with successful (paid) employment. No variables were associated with professional functioning (expressed as Presenteeism and Overall work impairment) in patients with CCD or haemophilia. CONCLUSION: Three-quarters of YA with CCD were successful in finding paid employment. Though absenteeism was low, YA with paid employment needs attention as a considerable part experienced work impairment.
Subject(s)
Blood Coagulation Disorders/physiopathology , Employment , Adolescent , Adult , Cognition , Disabled Persons , Efficiency , Female , Humans , Male , Netherlands , Quality of Life , Socioeconomic Factors , Young AdultABSTRACT
Cigarette smoking is a leading modifiable cause of death worldwide. We hypothesized that cigarette smoking induces extensive transcriptomic changes that lead to target-organ damage and smoking-related diseases. We performed a meta-analysis of transcriptome-wide gene expression using whole blood-derived RNA from 10,233 participants of European ancestry in six cohorts (including 1421 current and 3955 former smokers) to identify associations between smoking and altered gene expression levels. At a false discovery rate (FDR) <0.1, we identified 1270 differentially expressed genes in current vs. never smokers, and 39 genes in former vs. never smokers. Expression levels of 12 genes remained elevated up to 30 years after smoking cessation, suggesting that the molecular consequence of smoking may persist for decades. Gene ontology analysis revealed enrichment of smoking-related genes for activation of platelets and lymphocytes, immune response, and apoptosis. Many of the top smoking-related differentially expressed genes, including LRRN3 and GPR15, have DNA methylation loci in promoter regions that were recently reported to be hypomethylated among smokers. By linking differential gene expression with smoking-related disease phenotypes, we demonstrated that stroke and pulmonary function show enrichment for smoking-related gene expression signatures. Mediation analysis revealed the expression of several genes (e.g. ALAS2) to be putative mediators of the associations between smoking and inflammatory biomarkers (IL6 and C-reactive protein levels). Our transcriptomic study provides potential insights into the effects of cigarette smoking on gene expression in whole blood and their relations to smoking-related diseases. The results of such analyses may highlight attractive targets for treating or preventing smoking-related health effects.
Subject(s)
Cigarette Smoking/genetics , Gene Expression/drug effects , Adult , Aged , Cigarette Smoking/blood , Cohort Studies , CpG Islands , DNA Methylation , Female , Gene Expression Profiling , Gene Expression Regulation/genetics , Humans , Leukocytes/drug effects , Male , Middle Aged , Smoking/genetics , Transcriptome/drug effects , White People/geneticsABSTRACT
Genome-wide association studies (GWAS) have identified many susceptibility loci for cardiometabolic disorders. Most of the associated variants reside in non-coding regions of the genome including long non-coding RNAs (lncRNAs), which are thought to play critical roles in diverse biological processes. Here, we leveraged data from the available GWAS meta-analyses on lipid and obesity-related traits, blood pressure, type 2 diabetes, and coronary artery disease and identified 179 associated single-nucleotide polymorphisms (SNPs) in 102 lncRNAs (p-value < 2.3 × 10-7). Of these, 55 SNPs, either the lead SNP or in strong linkage disequilibrium with the lead SNP in the related loci, were selected for further investigations. Our in silico predictions and functional annotations of the SNPs as well as expression and DNA methylation analysis of their lncRNAs demonstrated several lncRNAs that fulfilled predefined criteria for being potential functional targets. In particular, we found evidence suggesting that LOC157273 (at 8p23.1) is involved in regulating serum lipid-cholesterol. Our results showed that rs4841132 in the second exon and cg17371580 in the promoter region of LOC157273 are associated with lipids; the lncRNA is expressed in liver and associates with the expression of its nearby coding gene, PPP1R3B. Collectively, we highlight a number of loci associated with cardiometabolic disorders for which the association may act through lncRNAs.
Subject(s)
Genetic Association Studies , Genetic Predisposition to Disease , Heart Diseases/genetics , Metabolic Diseases/genetics , RNA, Long Noncoding/genetics , Computational Biology/methods , DNA Methylation , Epigenesis, Genetic , Epistasis, Genetic , Gene Expression Profiling , Gene Expression Regulation , Genetic Variation , Genome-Wide Association Study , Humans , MicroRNAs/genetics , Molecular Sequence Annotation , Nucleic Acid Conformation , RNA Interference , RNA, Long Noncoding/chemistryABSTRACT
Desmopressin increases endogenous factor VIII levels in hemophilia A. Large inter-individual variation in the response to desmopressin is observed. Patients with a lower baseline factor VIII activity tend to show a reduced response, therefore, desmopressin is less frequently used in moderate hemophilia A patients (baseline factor VIII activity 1-5 international units/deciliter), even though factor VIII levels may rise substantially in some of them. We aim to describe the response to desmopressin in moderate hemophilia A patients and to identify predictors. We selected data on 169 patients with moderate hemophilia from the multicenter Response to DDAVP In non-severe hemophilia A patients: in Search for dEterminants (RISE) cohort study. Adequate response to desmopressin was defined as a peak factor VIII level ≥ 30, and excellent response as ≥ 50 international units/deciliter after desmopressin administration. We used univariate and multiple linear regression techniques to analyze predictors of the peak factor VIII level. Response was considered adequate in 68 patients (40%), of whom 25 showed excellent response (15%). Intravenous administration, age, pre-desmopressin factor VIII activity and von Willebrand factor antigen, peak von Willebrand factor activity and desmopressin-induced rise in von Willebrand factor antigen were significant predictors of peak factor VIII level and explained 65% of the inter-individual variation. In 40% of moderate hemophilia A patients, desmopressin response was adequate, thus it is important not to with-hold this group of patients from desmopressin responsiveness. Among the six predictors that we identified for desmopressin-induced factor VIII rise, factor VIII activity and desmopressin-induced rise in von Willebrand factor antigen had the strongest effect.
Subject(s)
Deamino Arginine Vasopressin/therapeutic use , Factor VIII/drug effects , Hemophilia A/drug therapy , Adolescent , Adult , Child , Deamino Arginine Vasopressin/adverse effects , Factor VIII/genetics , Factor VIII/metabolism , Hemophilia A/diagnosis , Humans , Middle Aged , Mutation , Predictive Value of Tests , Prognosis , Treatment Outcome , Young Adult , von Willebrand Factor/metabolismABSTRACT
INTRODUCTION: Diamond-Blackfan anemia (DBA) is characterized by hypoplastic anemia, congenital anomalies, and a predisposition for malignancies. Most of our understanding of this disorder stems from molecular studies combined with extensive data input from international patient registries. OBJECTIVES: To create an overview of the pediatric DBA population in the Netherlands. METHODS: Forty-three patients diagnosed with DBA from all Dutch university pediatric hospitals were included in this study, and their clinical and genetic characteristics were collected from patient records. RESULTS: Congenital malformations were present in 24 of 43 patients (55.8%). An underlying genetic defect was identified in 26 of 43 patients (60.5%), the majority of which were found in the RPS19 gene (12 of 43, 27.9%) with 1 patient carrying a mutation in a novel DBA candidate gene, RPL9. In 31 of 35 (88.6%) patients, an initial response to glucocorticoid treatment was observed. Six patients (14.0%) underwent hematopoietic stem cell transplantation, and eleven patients (11 of 43, 25.6%) became treatment-independent spontaneously. CONCLUSION: In agreement with previous reports, the Dutch pediatric DBA population is both clinically and genetically heterogeneous. National and international registries, together with more extensive genetic testing, are crucial to increase our understanding of genotype and phenotype correlations of this intriguing disorder.
Subject(s)
Anemia, Diamond-Blackfan/diagnosis , Anemia, Diamond-Blackfan/genetics , Adolescent , Anemia, Diamond-Blackfan/epidemiology , Anemia, Diamond-Blackfan/therapy , Child , Child, Preschool , Combined Modality Therapy , Congenital Abnormalities/diagnosis , Congenital Abnormalities/genetics , Female , Follow-Up Studies , Genetic Association Studies , Genetic Testing , Genetic Variation , Genotype , Humans , Infant , Infant, Newborn , Male , Netherlands/epidemiology , Phenotype , Polymorphism, Single Nucleotide , RegistriesABSTRACT
Bathers release bacteria in swimming pool water, but little is known about the fate of these bacteria and potential risks they might cause. Therefore, shower water was characterized and subjected to chlorination to identify the more chlorine-resistant bacteria that might survive in a chlorinated swimming pool and therefore could form a potential health risk. The total community before and after chlorination (1 mg Cl2 L-1 for 30 s) was characterized. More than 99% of the bacteria in the shower water were Gram-negative. The dominant bacterial families with a relative abundance of ≥10% of the total (non-chlorinated and chlorinated) communities were Flavobacteriaceae (24-21%), Xanthomonadaceae (23-24%), Moraxellaceae (12-11%) and Pseudomonadaceae (10-22%). The relative abundance of Pseudomonadaceae increased after chlorination and increased even more with longer contact times at 1 mg Cl2L-1. Therefore, Pseudomonadaceae were suggested to be relatively more chlorine resistant than the other identified bacteria. To determine which bacteria could survive chlorination causing a potential health risk, the relative abundance of the intact cell community was characterized before and after chlorination. The dominant bacterial families in the intact community (non-chlorinated and chlorinated) were Xanthomonadaceae (21-17%) and Moraxellaceae (48-57%). Moraxellaceae were therefore more chlorine resistant than the other identified intact bacteria present.
Subject(s)
Bacteria/growth & development , Halogenation , Water Microbiology , Water Purification , Chlorine , WaterABSTRACT
Carrier screening for hemoglobinopathies (HbPs; sickle cell disease and thalassemia) aims to facilitate autonomous reproductive decision-making. In the absence of a Dutch national HbP carrier screening program, some primary care midwives offer screening on an ad hoc basis. This qualitative descriptive study explores how pregnant women perceive an offer of HbP carrier screening by their midwife. Semi-structured interviews (n = 26) were conducted with pregnant women at risk of being a HbP carrier, and whom were offered screening at their booking appointment in one of two midwifery practices in Amsterdam. The results showed that half of the respondents were familiar with HbPs. Generally, women perceived the offer of HbP carrier screening as positive, and most women (n = 19) accepted screening. Seven declined, of whom two already knew their carrier status. Important reasons to accept screening were to obtain knowledge about their own carrier status and health of their unborn child, and the ease of the procedure. A multistep process of decision-making was observed, as many women did not give follow-up testing (e.g. partner, invasive diagnostics) much consideration while deciding on accepting or declining HbP screening. Women experienced information overload, and preferred receiving the information at a different moment (e.g. before the intake by a leaflet, or preconceptionally). In conclusion, while prenatal HbP carrier screening is perceived as positive, informed decision-making seems to be suboptimal, and both the content and timing of the information provided needs improvement.
Subject(s)
Hemoglobinopathies/genetics , Prenatal Diagnosis , Adult , Decision Making , Female , Humans , Mass Screening , Netherlands , Pregnancy , Prenatal Care , Primary Health Care , Qualitative Research , Risk FactorsABSTRACT
Genome-wide association studies (GWAS) have uncovered numerous genetic variants (SNPs) that are associated with blood pressure (BP). Genetic variants may lead to BP changes by acting on intermediate molecular phenotypes such as coded protein sequence or gene expression, which in turn affect BP variability. Therefore, characterizing genes whose expression is associated with BP may reveal cellular processes involved in BP regulation and uncover how transcripts mediate genetic and environmental effects on BP variability. A meta-analysis of results from six studies of global gene expression profiles of BP and hypertension in whole blood was performed in 7017 individuals who were not receiving antihypertensive drug treatment. We identified 34 genes that were differentially expressed in relation to BP (Bonferroni-corrected p<0.05). Among these genes, FOS and PTGS2 have been previously reported to be involved in BP-related processes; the others are novel. The top BP signature genes in aggregate explain 5%-9% of inter-individual variance in BP. Of note, rs3184504 in SH2B3, which was also reported in GWAS to be associated with BP, was found to be a trans regulator of the expression of 6 of the transcripts we found to be associated with BP (FOS, MYADM, PP1R15A, TAGAP, S100A10, and FGBP2). Gene set enrichment analysis suggested that the BP-related global gene expression changes include genes involved in inflammatory response and apoptosis pathways. Our study provides new insights into molecular mechanisms underlying BP regulation, and suggests novel transcriptomic markers for the treatment and prevention of hypertension.
Subject(s)
Blood Pressure/genetics , Genome-Wide Association Study , Hypertension/genetics , Transcriptome/genetics , Gene Expression Regulation , Genetic Predisposition to Disease , Genotype , Humans , Hypertension/pathology , Polymorphism, Single NucleotideABSTRACT
The functional consequences of trait associated SNPs are often investigated using expression quantitative trait locus (eQTL) mapping. While trait-associated variants may operate in a cell-type specific manner, eQTL datasets for such cell-types may not always be available. We performed a genome-environment interaction (GxE) meta-analysis on data from 5,683 samples to infer the cell type specificity of whole blood cis-eQTLs. We demonstrate that this method is able to predict neutrophil and lymphocyte specific cis-eQTLs and replicate these predictions in independent cell-type specific datasets. Finally, we show that SNPs associated with Crohn's disease preferentially affect gene expression within neutrophils, including the archetypal NOD2 locus.
Subject(s)
Lymphocytes/cytology , Neutrophils/cytology , Polymorphism, Single Nucleotide , Quantitative Trait Loci , Cell Line , Crohn Disease/genetics , Gene Expression Regulation , Genome-Wide Association Study/methods , Humans , Lymphocytes/metabolism , Neutrophils/metabolism , Nod2 Signaling Adaptor Protein/genetics , Nod2 Signaling Adaptor Protein/metabolism , Phenotype , Principal Component Analysis , Reproducibility of ResultsABSTRACT
OBJECTIVE: Osteoarthritis (OA) is the most common form of arthritis and the leading cause of disability in the elderly. Of all the joints, genetic predisposition is strongest for OA of the hand; however, only few genetic risk loci for hand OA have been identified. Our aim was to identify novel genes associated with hand OA and examine the underlying mechanism. METHODS: We performed a genome-wide association study of a quantitative measure of hand OA in 12 784 individuals (discovery: 8743, replication: 4011). Genome-wide significant signals were followed up by analysing gene and allele-specific expression in a RNA sequencing dataset (n=96) of human articular cartilage. RESULTS: We found two significantly associated loci in the discovery set: at chr12 (p=3.5 × 10-10) near the matrix Gla protein (MGP) gene and at chr12 (p=6.1×10-9) near the CCDC91 gene. The DNA variant near the MGP gene was validated in three additional studies, which resulted in a highly significant association between the MGP variant and hand OA (rs4764133, Betameta=0.83, Pmeta=1.8*10-15). This variant is high linkage disequilibrium with a coding variant in MGP, a vitamin K-dependent inhibitor of cartilage calcification. Using RNA sequencing data from human primary cartilage tissue (n=96), we observed that the MGP RNA expression of the hand OA risk allele was significantly lowercompared with the MGP RNA expression of the reference allele (40.7%, p<5*10-16). CONCLUSIONS: Our results indicate that the association between the MGP variant and increased risk for hand OA is caused by a lower expression of MGP, which may increase the burden of hand OA by decreased inhibition of cartilage calcification.
Subject(s)
Calcium-Binding Proteins/genetics , Cartilage, Articular/pathology , Extracellular Matrix Proteins/genetics , Genetic Predisposition to Disease/genetics , Hand Joints/pathology , Osteoarthritis/genetics , Adult , Aged , Alleles , Calcinosis/genetics , Carrier Proteins/genetics , Cytoskeletal Proteins , Female , Gene Expression/genetics , Gene Expression Profiling , Genome-Wide Association Study , Humans , Linkage Disequilibrium/genetics , Male , Middle Aged , Risk Factors , Sequence Analysis, RNA , Matrix Gla ProteinABSTRACT
AIMS/HYPOTHESIS: Tobacco smoking, a risk factor for diabetes, is an established modifier of DNA methylation. We hypothesised that tobacco smoking modifies DNA methylation of genes previously identified for diabetes. METHODS: We annotated CpG sites available on the Illumina Human Methylation 450K array to diabetes genes previously identified by genome-wide association studies (GWAS), and investigated them for an association with smoking by comparing current to never smokers. The discovery study consisted of 630 individuals (Bonferroni-corrected p = 1.4 × 10(-5)), and we sought replication in an independent sample of 674 individuals. The replicated sites were tested for association with nearby genetic variants and gene expression and fasting glucose and insulin levels. RESULTS: We annotated 3,620 CpG sites to the genes identified in the GWAS on type 2 diabetes. Comparing current smokers to never smokers, we found 12 differentially methylated CpG sites, of which five replicated: cg23161492 within ANPEP (p = 1.3 × 10(-12)); cg26963277 (p = 1.2 × 10(-9)), cg01744331 (p = 8.0 × 10(-6)) and cg16556677 (p = 1.2 × 10(-5)) within KCNQ1 and cg03450842 (p = 3.1 × 10(-8)) within ZMIZ1. The effect of smoking on DNA methylation at the replicated CpG sites attenuated after smoking cessation. Increased DNA methylation at cg23161492 was associated with decreased gene expression levels of ANPEP (p = 8.9 × 10(-5)). rs231356-T, which was associated with hypomethylation of cg26963277 (KCNQ1), was associated with a higher odds of diabetes (OR 1.06, p = 1.3 × 10(-5)). Additionally, hypomethylation of cg26963277 was associated with lower fasting insulin levels (p = 0.04). CONCLUSIONS/INTERPRETATION: Tobacco smoking is associated with differential DNA methylation of the diabetes risk genes ANPEP, KCNQ1 and ZMIZ1. Our study highlights potential biological mechanisms connecting tobacco smoking to excess risk of type 2 diabetes.
Subject(s)
DNA Methylation/genetics , Diabetes Mellitus, Type 2/genetics , Smoking/adverse effects , Aged , Female , Genome-Wide Association Study , Humans , Male , Middle AgedABSTRACT
Prevention of bleeding and joint damage in severe haemophilia is dependent on adherence to prophylactic replacement therapy. The aim of this study was to assess adherence to prophylaxis, including associations with age, bleeding and clotting factor consumption (CFC). In three Dutch haemophilia centres, semi-structured interviews about adherence to prophylaxis in the previous 2 weeks were conducted with patients or parents of a child with haemophilia. Patients were classified, according to pre-specified definitions, as adherent, sub-optimally adherent or non-adherent based on missing, timing, and dose of infusions. Association of annual bleeding rates, mean CFC, person performing the infusion (parents verus patients) with adherence categories were analysed. Overall, 241 patients with haemophilia using prophylaxis were studied. Parents were more adherent (66%; n = 48/73) than patients (43%; n = 72/168). Sub-optimal adherence occurred in 29% of parents and 37% of patients and was characterized by changes in timing of infusion (mostly from morning to evening), while missing <6% of infusions. Non-adherence occurred less often: in 5% of parents and 20% of patients. Reduced adherence was associated with lower CFC, but not with joint bleeding. In conclusion, non-adherence in haemophilia was relatively rare, yet 1/3 of patients struggled to administer prophylaxis at the appropriate time of day.