Description:
Genetic determinants of blood pressure are poorly defined. We undertook a large-scale, gene-centric analysis to identify loci and pathways associated with ambulatory systolic and diastolic blood pressure. We measured 24-hour ambulatory blood pressure in 2020 individuals from 520 white European nuclear families (the Genetic Regulation of Arterial Pressure of Humans in the Community Study) and genotyped their DNA using the Illumina HumanCVD BeadChip array, which contains approximate to 50 000 single nucleotide polymorphisms in >2000 cardiovascular candidate loci. We found a strong association between rs13306560 polymorphism in the promoter region of MTHFR and CLCN6 and mean 24-hour diastolic blood pressure; each minor allele copy of rs13306560 was associated with 2.6 mm Hg lower mean 24-hour diastolic blood pressure (P=1.2 x 10(-8)). rs13306560 was also associated with clinic diastolic blood pressure in a combined analysis of 8129 subjects from the Genetic Regulation of Arterial Pressure of Humans in the Community Study, the CoLaus Study, and the Silesian Cardiovascular Study (P=5.4 x 10(-6)). Additional analysis of associations between variants in gene ontology-defined pathways and mean 24-hour blood pressure in the Genetic Regulation of Arterial Pressure of Humans in the Community Study showed that cell survival control signaling cascades could play a role in blood pressure regulation. There was also a significant overrepresentation of rare variants (minor allele frequency: <0.05) among polymorphisms showing at least nominal association with mean 24-hour blood pressure indicating that a considerable proportion of its heritability may be explained by uncommon alleles. Through a large-scale gene-centric analysis of ambulatory blood pressure, we identified an association of a novel variant at the MTHFR/CLNC6 locus with diastolic blood pressure and provided new insights into the genetic architecture of blood pressure.
Description:
Essential hypertension is a complex, multifactorial disease with a strong genetic component. Fibroblast growth factor 1 gene (FGF1) is one of the most relevant candidates having been associated not only with familial susceptibility to hypertension but also with up-regulation within the glomerulus of the human hypertensive kidney/Circulation 2007;116:1915e24/. We have hypothesised that systematic analysis of genes interacting with FGF1 may uncover novel variants underlying essential hypertension. Seventy-nine common (minor allele frequency$0.1) tagging (r2$0.8) and functional single nucleotide polymorphisms (SNPs) spanning eight critical components of the FGF (fibroblast growth factor) pathway (FGF2, FGFR1, FGFR2, FGFR3, FGFR4, FGFBP1, FIBP, SPRY1) were genotyped by MALDI-TOF mass spectrometry in 629 subjects from 207 Polish hypertensive families (Silesian Hypertension Study d SHS). 83.5% of genotyped SNPs that passed quality control filters provided 92.9% genetic coverage of FGF pathway loci. Family-based analysis in SHS revealed that alleles of three SNPs (rs2956724, rs2245964 and rs16892645) in two loci (FGFR1 and FGFBP1) were transmitted to hypertensive offspring more frequently than expected by chance. However, only one association survived correction for multiple testing e major allele of rs16892645 in FGFBP1 was over-transmitted from heterozygous parents to hypertensive offspring more frequently than expected by chance (p¼0.0048, false discovery rate<0.25). The association between rs16892645 and hypertension was replicated in an independent cohort of 807 Polish subjects from Silesian Cardiovascular Study d each major allele copy of rs16892645 increased the odds of hypertension approximately by 1.5 (odds ratio: 1.5; 95% CI: 1.1 to to 2.2, p¼0.04). Association between FGFBP1 and hypertension was also apparent at the protein expression level d compared with normotensive patients, hypertensives from Silesian Renal Tissue Bank showed approximately 1.4-fold higher renal abundance of FGFBP1 in Western blotting (p¼0.001). Immunohistochemical analysis revealed that hypertension-related up-regulation of FGFBP1 was exclusive to renal glomeruli. These data show that FGFBP1da gene that encodes a carrier protein for FGF1 d is associated with human hypertension. We also reveal that up-regulation of FGFBP1 maps to the same histological compartment where FGF1 was shown to be most abundant (renal glomeruli). Our study also proves that systematic genetic analysis of signalling pathways is a strategy with a potential to identify novel molecular mechanisms underlying blood pressure elevation.
Description:
Objectives: Men show higher rates of cardiovascular morbidity and mortality than pre-menopausal women and this sexual dimorphism may be related to sex-specific effects of sex steroids on cardiovascular risk factors. Unlike androgens, estrogens were not extensively investigated in relation to cardiovascular phenotypes in men.
Description:
Genome-wide association studies (GWAS) have identified >100 loci of chronic kidney disease-defining traits (CKD-dt). Molecular mechanisms underlying these associations remain elusive. Using 280 kidney transcriptomes and 9958 gene expression profiles from 44 non-renal tissues we uncover gene expression partners (eGenes) for 88.9% of CKD-dt GWAS loci. Through epigenomic chromatin segmentation analysis and variant effect prediction we annotate functional consequences to 74% of these loci. Our colocalisation analysis and Mendelian randomisation in >130,000 subjects demonstrate causal effects of three eGenes (NAT8B, CASP9 and MUC1) on estimated glomerular filtration rate. We identify a common alternative splice variant in MUC1 (a gene responsible for rare Mendelian form of kidney disease) and observe increased renal expression of a specific MUC1 mRNA isoform as a plausible molecular mechanism of the GWAS association signal. These data highlight the variants and genes underpinning the associations uncovered in GWAS of CKD-dt.
Description:
Genome-wide association studies (GWAS) have identified >100 loci of chronic kidney disease-defining traits (CKD-dt). Molecular mechanisms underlying these associations remain elusive. Using 280 kidney transcriptomes and 9958 gene expression profiles from 44 non-renal tissues we uncover gene expression partners (eGenes) for 88.9% of CKD-dt GWAS loci. Through epigenomic chromatin segmentation analysis and variant effect prediction we annotate functional consequences to 74% of these loci. Our colocalisation analysis and Mendelian randomisation in >130,000 subjects demonstrate causal effects of three eGenes (NAT8B, CASP9 and MUC1) on estimated glomerular filtration rate. We identify a common alternative splice variant in MUC1 (a gene responsible for rare Mendelian form of kidney disease) and observe increased renal expression of a specific MUC1 mRNA isoform as a plausible molecular mechanism of the GWAS association signal. These data highlight the variants and genes underpinning the associations uncovered in GWAS of CKD-dt.
Description:
Nephrons scar and involute during aging, increasing the risk of chronic kidney disease. Little is known, however, about genetic mechanisms of kidney aging. We sought to define the signatures of age on the renal transcriptome using 563 human kidneys. The initial discovery analysis of 260 kidney transcriptomes from the TRANScriptome of renaL humAn TissuE Study (TRANSLATE) and the Cancer Genome Atlas identified 37 age-associated genes. For 19 of those genes, the association with age was replicated in 303 kidney transcriptomes from the Nephroseq resource. Surveying 42 nonrenal tissues from the Genotype–Tissue Expression project revealed that, for approximately a fifth of the replicated genes, the association with age was kidney-specific. Seventy-three percent of the replicated genes were associated with functional or histological parameters of age-related decline in kidney health, including glomerular filtration rate, glomerulosclerosis, interstitial fibrosis, tubular atrophy, and arterial narrowing. Common genetic variants in four of the age-related genes, namely LYG1, PPP1R3C, LTF and TSPYL5, correlated with the trajectory of age-related changes in their renal expression. Integrative analysis of genomic, epigenomic, and transcriptomic information revealed that the observed age-related decline in renal TSPYL5 expression was determined both genetically and epigenetically. Thus, this study revealed robust molecular signatures of the aging kidney and new regulatory mechanisms of age-related change in the kidney transcriptome.
Description:
Nephrons scar and involute during aging, increasing the risk of chronic kidney disease. Little is known, however, about genetic mechanisms of kidney aging. We sought to define the signatures of age on the renal transcriptome using 563 human kidneys. The initial discovery analysis of 260 kidney transcriptomes from the TRANScriptome of renaL humAn TissuE Study (TRANSLATE) and the Cancer Genome Atlas identified 37 age-associated genes. For 19 of those genes, the association with age was replicated in 303 kidney transcriptomes from the Nephroseq resource. Surveying 42 nonrenal tissues from the Genotype–Tissue Expression project revealed that, for approximately a fifth of the replicated genes, the association with age was kidney-specific. Seventy-three percent of the replicated genes were associated with functional or histological parameters of age-related decline in kidney health, including glomerular filtration rate, glomerulosclerosis, interstitial fibrosis, tubular atrophy, and arterial narrowing. Common genetic variants in four of the age-related genes, namely LYG1, PPP1R3C, LTF and TSPYL5, correlated with the trajectory of age-related changes in their renal expression. Integrative analysis of genomic, epigenomic, and transcriptomic information revealed that the observed age-related decline in renal TSPYL5 expression was determined both genetically and epigenetically. Thus, this study revealed robust molecular signatures of the aging kidney and new regulatory mechanisms of age-related change in the kidney transcriptome.
Description:
Telomere length is recognized as a marker of biological age, and shorter mean leukocyte telomere length is associated with increased risk of cardiovascular disease. It is unclear whether repeated exposure to ultra-endurance aerobic exercise is beneficial or detrimental in the long-term and whether it attenuates biological aging. We quantified 67 ultra-marathon runners' and 56 apparently healthy males' leukocyte telomere length (T/S ratio) using real-time quantitative PCR. The ultra-marathon runners had 11% longer telomeres (T/S ratio) than controls (ultra-marathon runners: T/S ratio = 3.5±0.68, controls: T/S ratio = 3.1±0.41;
Description:
Telomere length is recognized as a marker of biological age, and shorter mean leukocyte telomere length is associated with increased risk of cardiovascular disease. It is unclear whether repeated exposure to ultra-endurance aerobic exercise is beneficial or detrimental in the long-term and whether it attenuates biological aging. We quantified 67 ultra-marathon runners' and 56 apparently healthy males' leukocyte telomere length (T/S ratio) using real-time quantitative PCR. The ultra-marathon runners had 11% longer telomeres (T/S ratio) than controls (ultra-marathon runners: T/S ratio = 3.5±0.68, controls: T/S ratio = 3.1±0.41;
Description:
Fibroblast growth factor 21 (FGF21) is a novel master regulator of metabolic profile. The biological actions of FGF21 are elicited upon its klotho beta (KLB)-facilitated binding to FGF receptor 1 (FGFR1), FGFR2 and FGFR3. We hypothesised that common polymorphisms in the FGF21 signalling pathway may be associated with metabolic risk. At the screening stage, we examined associations between 63 common single-nucleotide polymorphisms (SNPs) in five genes of this pathway (FGF21, KLB, FGFR1, FGFR2, FGFR3) and four metabolic phenotypes (LDL cholesterol-LDL-C, HDL-cholesterol-HDL-C, triglycerides and body mass index) in 629 individuals from Silesian Hypertension Study (SHS). Replication analyses were performed in 5478 unrelated individuals of the Swiss CoLaus cohort (imputed genotypes) and in 3030 directly genotyped individuals of the German Myocardial Infarction Family Study (GerMIFS). Of 54 SNPs that met quality control criteria after genotyping in SHS, 4 (rs4733946 and rs7012413 in FGFR1; rs2071616 in FGFR2 and rs7670903 in KLB) showed suggestive association with LDL-C (P=0.0006, P=0.0013, P=0.0055, P=0.011, respectively) and 1 (rs2608819 in KLB) was associated with body mass index (P=0.011); all with false discovery rate q<0.5. Of these, only one FGFR2 polymorphism (rs2071616) showed replicated association with LDL-C in both CoLaus (P=0.009) and men from GerMIFS (P=0.017). The direction of allelic effect of rs2071616 upon LDL-C was consistent in all examined populations. These data show that common genetic variations in FGFR2 may be associated with LDL-C in subjects of white European ancestry
Description:
Objective: Amongst middle-aged men, haplogroup I is associated with approximate to 50% higher risk of coronary artery disease than other paternal lineages of Y chromosome. We hypothesised that carriers of haplogroup I had higher levels of aggression and estrogens and/or lower levels of androgens early in life and thus might be more prone to cardiovascular disease than men with other lineages of Y chromosome. Methods: We reconstructed phylogenetic tree of the Y chromosome in > 1000 young apparently healthy white men from the general population. Each Y chromosome was classified into one of 13 most common European lineages. Androgens (DHEA-S, androstenedione, total testosterone) and their metabolites (total estradiol, estrone) were measured by radioimmunoassays. Information on five dimensions of aggression (total, physical, verbal, anger and hostility) was collected using Buss and Perry questionnaire. Results: Approximately 17% men inherited haplogroup I from their fathers. Carriers of haplogroup I showed lower scores of verbal aggression than men with other haplogroups (beta = -0.72, SE = 0.29, P = 0.012) and when further compared to carriers of most common R1a lineage and other haplogroups (beta = -1.03, SE = 0.34, P = 0.003). However, these associations did not survive a correction for multiple testing. Sex steroids did not show even nominal level of association with haplogroup I. Conclusion: Our data show no overall association between haplogroup I and sex-related phenotypes in young white men. These results also suggest that the previously identified association between haplogroup I and coronary artery disease is not likely mediated by unfavourable profile of sex steroids or heightened aggression early in life. (C) 2014 Elsevier Ireland Ltd. All rights reserved.
Description:
Objective-A rare mutation in low-density lipoprotein receptor-related protein 6 gene (LRP6) was identified as the primary molecular defect underlying monogenic form of coronary artery disease. We hypothesized that common variants in LRP6 could predispose subjects to elevated LDL-cholesterol (LDL-C). Methods and Results-Twelve common ( minor allele frequency >= 0.1) single nucleotide polymorphisms in LRP6 were genotyped in 703 individuals from 213 Polish pedigrees (Silesian Cardiovascular Study families). The family-based analysis revealed that the minor allele of rs10845493 clustered with elevated LDL-C in offspring more frequently than expected by chance (P=0.0053). The quantitative analysis restricted to subjects free of lipid-lowering treatment confirmed the association between rs10845493 and age-, sex-, and BMI-adjusted circulating levels of LDL-C in families as well as 2 additional populations - 218 unrelated subjects from Silesian Cardiovascular Study replication panel and 1138 individuals from Young Men Cardiovascular Association cohort (P=0.0268, P=0.0476, and P=0.0472, respectively). In the inverse variance weighted meta-analysis of the 3 populations each extra minor allele copy of rs10845493 was associated with 0.14 mmol/L increase in age-, sex-, and BMI-adjusted LDL-C (SE=0.05, P=0.0038). Conclusions-Common polymorphism in the gene underlying monogenic form of coronary artery disease impacts on risk of LDL-C elevation. (Arterioscler Thromb Vasc Biol. 2009;29:1316-1321.)
Description:
Background: Leukocyte telomere length is a marker of biological ageing and its shortening is associated with cardiovascular disease. Engagement in regular moderate-intensity physical activity is a recognised method of cardiovascular disease prevention. However, it is not clear whether repeated exposure to ultra-strenuous physical exercise is beneficial long-term and whether it may attenuate biological ageing. Methods: We compared leukocyte telomere length in context of inflammation and endothelial dysfunction between 67 male ultra-marathon runners and 67 age-, sex- and BMI-matched apparently healthy controls. Genomic DNA was extracted from peripheral blood and leukocyte telomere length was measured by quantitative polymerase chain reaction assays. Adhesion molecules (sICAM-1, sE-selectin) and inflammatory markers (IL-6, C-reactive protein) concentrations were measured in 67 ultra-marathon runners by quantitative sandwich enzyme immunoassay technique, high-sensitive immunoassay and ultra-sensitive double antibody sandwich ELISA, respectively. Results: Adjusted (for age, BMI, blood pressure and lipids) leukocyte telomere length was approximately 13.8% greater in the ultra-marathon runners than in the controls (P<0.001). This translates into approximately 32.9 years difference in age-related telomere length attrition. There was a strong negative linear correlation between sICAM-1 and leukocyte telomere length in the ultra-marathon runners (r=-0.33; P=0.007) and this association retained its statistical significance after adjustment for age, BMI, blood pressure and lipids in multiple regression (P=0.026). Conclusion: Prolonged, intense physical exercise may attenuate cellular ageing possibly through a protective effect on endothelial function.