Venous Thromboembolism Susceptibility Research Articles

The blood proteo-genomic architecture of venous thromboembolism

Background and Aims : Genome-wide association studies (GWAS) have identified dozens of genetic loci associated with venous thromboembolism (VTE) susceptibility. The functional impact of these genetic variants is not completely characterized. We hypothesized that VTE susceptibility loci have an important influence on the human blood proteome.

Exome Sequencing Studies Identify Mutations in STAB2 As a Genetic Risk for Venous Thromboembolic Disease

Deep vein thrombosis and pulmonary embolism, collectively referred to as venous thromboembolism (VTE), are the third leading cause of cardiovascular death in the United States. Genetic factors account for 50-60% of VTE risk and a recent meta-analysis of genome-wide association studies confirmed that common variants in F5, ABO, F2 and seven other very low effect size loci are associated with VTE. Rare mutations in the anticoagulant genes PROC (protein C), PROS1 (protein S) and SERPINC1 (antithrombin III) have been linked to highly penetrant VTE risk in family studies but no genome-wide study of rare variants has been reported to date.We performed whole exome sequencing (WES) in 373 unrelated individuals of European ancestry with well characterized unprovoked VTE and compared results to a previously genome sequenced control cohort of 5784 unrelated Europeans. We then identified single nucleotide variants, small insertion or deletions that were present at allele frequencies less than 0.005% in ExAC and had equal sequencing coverage between groups. Using a dominant model and a collapsing association analysis, we looked for genes that were more likely to harbor “knockout” (frame shift, nonsense, splice site and damaging missense) mutations in cases versus controls. Strikingly, ranked by p-value, among 17,395 genes tested, the top 4 genes were PROS1 (P= 2.01E-09, odds ratio: 11.8), STAB2 (P=2.70E-7, odds ratio 3.37), PROC (P=3.24E-05, odds ratio 11.0) and SERPINC1 (P=1.10E-04, odds ratio 8.5), Figure. These findings suggest that heterozygous deficiency for the STAB2 encoded protein, stabilin-2, confers VTE susceptibility similar to the previously well described phenotypes of heterozygous protein C, protein S and antithrombin III deficiency.Stabilin-2 is a single transmembrane glycoprotein scavenger receptor expressed on venous endothelium of liver sinusoids and spleen. We detected damaging STAB2 mutations in 29 (7%) VTE cases versus 141 (2%) of controls. Common and uncommon variants in STAB2 have been associated with elevated plasma von Willebrand factor (VWF) and coagulation factor VIII levels, which are known risk factors for VTE. Stabilin-2 is implicated as a clearance receptor for VWF, so that haploinsufficiency of stabilin-2 may increase plasma VWF half-life. To test this hypothesis, we examined 1162 individuals in the Twins UK Study (VTE status unknown) with available whole genome sequencing data and measured their plasma VWF levels by AlphaLISA. VWF levels were adjusted by log transformation and ABO blood type tagging SNPs. We identified 38 individuals (3.2%, all heterozygous) with rare damaging variants in STAB2. VWF levels were significantly higher in individuals (N=30) with rare STAB2 variants compared to those without (N=1016) (Mann-Whitney, P= 0.0046).To further examine stabilin-2 function in vivo, we compared Stab2 deficient mice (Stab2 -/-) to wild type (Stab2 +/+) controls. Stab2 -/- mice had elevated plasma levels of factor VIII:C (118%, p=0.0006), but no differences in VWF (p=0.58). Next, we examined thrombosis in a mouse model where venous blood clotting was induced by inferior vena cava stenosis. Thrombi were weighed and longitudinal sections were analyzed by quantitative immunohistochemistry 24 hours post-stenosis. Stab2 -/- mice developed significantly larger thrombi than Stab2 +/+ mice (194%, n=19, p=0.003) but no difference in DVT incidence (64% vs 61%, P= 0.85). Despite equivalent hematocrit (P= 0.91) and white type thrombus (P> 0.05), thrombi from Stab2 -/- mice were comprised of more red type thrombus (185%, P= 0.004).Through an unbiased analysis of whole exome sequencing in 6,157 individuals, this studyconfirms the role of haploinsufficiency of PROC, PROS1 and SERPINC1 for VTE susceptibility and identifies STAB2 deficiency as a potential new risk factor. Analysis of an independent human cohort of 1162 Europeans demonstrates that STAB2 haploinsufficiency is associated with elevated VWF levels, a known risk factor for VTE. Finally, a mouse model of Stab2 deficiency demonstrates enhanced thrombosis, though without an association with elevated VWF levels. Taken together, these results suggest that rare genetic variants in STAB2 collectively play a role in individuals with unprovoked VTE by prolonging the plasma half-life of procoagulant factors such as VWF, adding an important new gene to the short list of known risk factors for this common disease. [Display omitted] DisclosuresReitsma:Leiden University Medical Center; VarmX B.V.: Equity Ownership, Patents & Royalties: co-inventor on a patent application related to this abstract.

Endothelial nitric oxide synthase polymorphism and venous thromboembolism: A meta-analysis of 9 studies involving 3993 subjects.

Endothelial nitric oxide synthase (eNOS) polymorphism may influence the risk of venous thromboembolism (VTE). However, data from published studies with low statistical power are inconclusive. The present meta-analysis aimed to assess the relationship between eNOS polymorphism and the risk of VTE. Case-control studies evaluating the association between the eNOS polymorphism and VTE were searched in PubMed, Embase, Web of Science, Google Scholar, Wanfang, Chinese National Knowledge Infrastructure (CNKI), the Chongqing VIP Chinese Science and Technology Periodical Database (VIP), and Chinese Biomedical Literature Database (CBM). A total of 1588 cases and 2405 controls from 9 studies were included in the analysis. The results showed that eNOS G894T polymorphism was related to VTE susceptibility and the difference was statistically significant [T vs G: OR = 1.41, 95% CI (1.13, 1.75), P = 0.002; TT + GG vs TG: OR = 0.71, 95% CI (0.60, 0.84), P = 0.000; TT + TG vs GG: OR = 1.45, 95% CI (1.23, 1.70), P = 0.000]. Additionally, eNOS Intron 4 VNTR polymorphism was related to VTE susceptibility and the difference was statistically significant [4b4b vs 4a4a + 4a4b: OR = 2.77, 95% CI (1.01, 7.61), P = 0.048]. ENOS G894T and eNOS Intron 4 VNTR polymorphisms were associated with VTE susceptibility, especially in Asian populations. However, multicenter studies with larger samples should be conducted to further clarify this association and verify our findings.

Association between FSAP 1601G>A polymorphism and venous thromboembolism risk: A meta-analysis.

Previous several studies have shown that factor VII-activating protease (FSAP) gene 1601G>A polymorphism is related to the occurrence of venous thromboembolism, but the results are inconsistent and controversial. Therefore, we conducted a meta-analysis to explore the association between FSAP 1601G>A polymorphism and venous thromboembolism susceptibility. We managed a systematic literature search through Pubmed, Embase, Web of Science, China National Knowledge Infrastructure, and WanFang databases to collect research data related to FSAP gene 1601G>A polymorphism and susceptibility to venous thromboembolism published before May 2019. Data analysis was performed through Revman 5.3 and Stata 12.0 software, the pooled odd ratios and 95% confidence intervals were calculated. Additionally, the sensitivity analysis and publication bias assessment were also performed. A total of seven case-control studies were included and evaluated, including 2411 venous thromboembolism cases and 2850 controls. The meta-analysis results revealed that the FSAP 1601G>A mutation is associated with venous thromboembolism risk, and statistically significance was observed under three genetic comparison models (A: G, odds ratio: 1.33, 95% confidence interval: 1.07-1.66; GA: GG, odds ratio: 1.34, 95% confidence interval: 1.06-1.68; and GA + AA: GG, odds ratio: 1.33, 95% confidence interval: 1.06-1.66). This study demonstrated that the FSAP 1601G>A polymorphism may be associated with venous thromboembolism susceptibility.

Venous thromboembolism risk associated with ABO, F11 and FGG loci.

: The current study aims to evaluate, for the first time in the Portuguese population, the association with venous thromboembolism (VTE) of five well known and replicated VTE-associated single nucleotide polymorphisms (SNPs) in genes ABO, F11 and FGG. A population sample of 96 cases of VTE, without strong or moderate inherited or noninherited predisposing factors, and 148 healthy controls were analyzed for variants in genes ABO (rs2519093; rs8176719), F11 (rs2036914; rs2289252) and FGG (rs2066865). SNPs were genotyped by real-time PCR with TaqMan probes or by PCR-restriction fragment length polymorphism. Logistic regression, adjusted for age and sex, revealed nominal significant association between the ABO rs8176719 C-allele and VTE in the additive model [odds ratio (OR) 1.62; P = 0.015] and significant association in the dominant model (OR 2.68; P = 0.001). A nominal significant association with VTE was found for the FGG rs2066865 minor T-allele in the dominant model (OR 1.82; P = 0.034). A genetic risk score created by using subjects who carry one or any combination of two to four risk alleles showed a cumulative effect on VTE: OR 2.31 (P = 0.025) and OR 3.23 (P = 0.0016), respectively, compared with individuals who have none of the risk alleles. Our data suggest that SNPs ABO rs8176719 and FGG rs2066865 may contribute individually to the VTE susceptibility in the Portuguese population. A genetic risk score combining the VTE-associated FGG and ABO alleles improved the risk prediction of VTE.

Mitochondrial genome association study with peripheral arterial disease and venous thromboembolism

Background and aimsPeripheral arterial disease (PAD) and venous thromboembolism (VTE) are vascular traits sharing common modifiable and non-modifiable risk factors. These vascular pathologies have known nuclear-encoded genetic risk factors and the mitochondrial DNA may account for part of the missing heritability. To determine if PAD and VTE have a dual genetic control (mitochondrial and nuclear), we hereby investigated the association of mitochondrial DNA polymorphisms and haplogroups with these vascular traits. MethodsThe association of mitochondrial single nucleotide polymorphisms (mtSNPs) and haplogroups was tested in 1652 PAD cases and 1629 controls from the eMERGE PAD genome-wide association study (GWAS), and 1241 VTE cases and 1278 controls from the GENEVA GWAS of venous thrombosis (dbGaP accession numbers phs000203.v1.p1 and phs000289.v2.p1, respectively). Results66 and 72 mtSNPs passed quality control filters and were tested for association with PAD and VTE, respectively. Significant evidence of population stratification could not be detected in both datasets. Three mtSNPs (m.477T > C, m.9667A > G, and m.10915T > C) were nominally associated (3.01 × 10−3 ≤ pa ≤ 3.96 × 10−2) with PAD in the logistic regression adjusted for confounding factors, and m.11914G > A was nominally associated (pa = 4.14 × 10−2) with VTE. None of the nine major mitochondrial haplogroups were associated with either PAD or VTE. ConclusionUnlike other vascular diseases such as stroke and diabetes, these results suggest that common mitochondrial variants individually or in combination do not play a major role in PAD and VTE susceptibility.

Apolipoprotein(a) Kringle-IV Type 2 Copy Number Variation Is Associated with Venous Thromboembolism.

In addition to the established association between high lipoprotein(a) [Lp(a)] concentrations and coronary artery disease, an association between Lp(a) and venous thromboembolism (VTE) has also been described. Lp(a) is controlled by genetic variants in LPA gene, coding for apolipoprotein(a), including the kringle-IV type 2 (KIV-2) size polymorphism. Aim of the study was to investigate the role of LPA gene KIV-2 size polymorphism and single nucleotide polymorphisms (SNPs) (rs1853021, rs1800769, rs3798220, rs10455872) in modulating VTE susceptibility. Five hundred and sixteen patients with VTE without hereditary and acquired thrombophilia and 1117 healthy control subjects, comparable for age and sex, were investigated. LPA KIV-2 polymorphism, rs3798220 and rs10455872 SNPs were genotyped by TaqMan technology. Concerning rs1853021 and rs1800769 SNPs, PCR-RFLP assay was used. LPA KIV-2 repeat number was significantly lower in patients than in controls [median (interquartile range) 11(6–17) vs 15(9–25), p<0.0001]. A significantly higher prevalence of KIV-2 repeat number ≤7 was observed in patients than in controls (33.5% vs 15.5%, p<0.0001). KIV-2 repeat number was independently associated with VTE (p = 4.36 x10-9), as evidenced by the general linear model analysis adjusted for transient risk factors. No significant difference in allele frequency for all SNPs investigated was observed. Haplotype analysis showed that LPA haplotypes rather than individual SNPs influenced disease susceptibility. Receiver operating characteristic curves analysis showed that a combined risk prediction model, including KIV-2 size polymorphism and clinical variables, had a higher performance in identifying subjects at VTE risk than a clinical-only model, also separately in men and women.

Meta-analysis of 65,734 Individuals Identifies TSPAN15 and SLC44A2 as Two Susceptibility Loci for Venous Thromboembolism

Venous thromboembolism (VTE), the third leading cause of cardiovascular mortality, is a complex thrombotic disorder with environmental and genetic determinants. Although several genetic variants have been found associated with VTE, they explain a minor proportion of VTE risk in cases. We undertook a meta-analysis of genome-wide association studies (GWASs) to identify additional VTE susceptibility genes. Twelve GWASs totaling 7,507 VTE case subjects and 52,632 control subjects formed our discovery stage where 6,751,884 SNPs were tested for association with VTE. Nine loci reached the genome-wide significance level of 5× 10(-8) including six already known to associate with VTE (ABO, F2, F5, F11, FGG, and PROCR) and three unsuspected loci. SNPs mapping to these latter were selected for replication in three independent case-control studies totaling 3,009 VTE-affected individuals and 2,586 control subjects. This strategy led to the identification and replication of two VTE-associated loci, TSPAN15 and SLC44A2, with lead risk alleles associated with odds ratio for disease of 1.31 (p = 1.67× 10(-16)) and 1.21 (p = 2.75× 10(-15)), respectively. The lead SNP at the TSPAN15 locus is the intronic rs78707713 and the lead SLC44A2 SNP is the non-synonymous rs2288904 previously shown to associate with transfusion-related acute lung injury. We further showed that these two variants did not associate with known hemostatic plasma markers. TSPAN15 and SLC44A2 do not belong to conventional pathways for thrombosis and have not been associated to other cardiovascular diseases nor related quantitative biomarkers. Our findings uncovered unexpected actors of VTE etiology and pave the way for novel mechanistic concepts of VTE pathophysiology.

Association between the plasminogen activator inhibitor-1 4G/5G polymorphism and risk of venous thromboembolism: A meta-analysis

IntroductionThe plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism was considered to be associated with risk of venous thromboembolism (VTE), while evidence remains inadequate. To provide a more accurate estimation of this relationship, we performed an updated meta-analysis of all eligible studies. Materials and MethodsA systematical search was performed in PubMed, EMBASE, Wanfang, China National Knowledge Infrastructure (CNKI) and Cqvip databases to identify relevant studies published before March 6th 2014. The odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using the fixed/random-effects model using Review Manager 5.1 and STATA 12.0. ResultsA total of 34 studies with 3561 cases and 5693 controls were analyzed. Overall, significant association between the PAI-1 4G/5G variant and VTE risk in total population (dominant model: OR=1.32, 95%CI: 1.13-1.54) was observed. And this variant was also related to the deep vein thrombosis risk (dominant model: OR=1.60, 95%CI: 1.24-2.06, P=0.0003). In the subgroup analyses on ethnicity, significant results were obtained in both Asians (dominant model: OR=2.08, 95%CI: 1.29-3.35, P=0.003) and Caucasians (dominant model: OR=1.31, 95%CI: 1.10-1.56, P=0.003). However, no significant association was found in patients with provoked VTE. In terms of subgroup analyses on co-existence of other thrombotic risk factors, the PAI-1 4G/5G polymorphism was significantly associated with VTE risk in patients with factor V Leiden mutation (dominant model: OR=1.72, 95%CI: 1.17-2.53), but not in patients with cancer or surgery. ConclusionOur findings demonstrate the role of PAI-1 4G/5G polymorphism being a risk candidate locus for VTE susceptibility, especially in patients with other genetic thrombophilic disorders.

Genome‐wide linkage scan in affected sibling pairs identifies novel susceptibility region for venous thromboembolism: Genetics In Familial Thrombosis study

Venous thromboembolism (VTE) is a multicausal disorder involving environmental and genetic risk factors. In many thrombophilic families the clustering of thrombotic events cannot be explained by known genetic risk factors, indicating that some remain to be discovered. We aimed to identify novel thrombosis susceptibility alleles in a large panel of small thrombophilic families: the Genetics In Familial Thrombosis (GIFT) study. In the GIFT study, 201 families were recruited consisting of 438 siblings with an objectively confirmed VTE at a young age. Multipoint linkage analysis (402 SSR markers) and fine mapping were performed, followed by genotyping of tagging SNPs in positional candidate genes. Established genetic risk factors such as factor V Leiden, ABO blood group non-O, prothrombin 20210A, fibrinogen gamma 10034T and deficiencies of antithrombin, protein C and protein S were more frequent in GIFT patients than in unselected VTE patients. Linkage supported the presence of novel thrombosis susceptibility loci on 7p21.3-22.2 (LOD score=3.23) and Xq24-27.3 (LOD score=1.95). Simulation analysis showed that the chr7 signal was genome-wide statistically significant (P=0.022). Tagging SNPs (n=157) in eight positional candidate genes (LOD drop 1.5 regions) were genotyped in GIFT patients and 332 healthy controls. Five chr7 SNPs associated with VTE. SNP THSD7A rs2074597 was responsible for part of the chr7 signal. The GIFT panel is rich in established genetic risk factors for VTE, but genetic factors remain unidentified in many families. Genome-wide linkage failed to identify the previously established genetic risk factors for VTE, but identified a novel VTE susceptibility locus on chr7.

A multi-stage multi-design strategy provides strong evidence that the BAI3 locus is associated with early-onset venous thromboembolism.

Factor VIII (FVIII) and von Willebrand factor (VWF) are two known quantitative risk factors for venous thromboembolism (VTE). To identify new loci that could contribute to VTE susceptibility and to modulating FVIII and/or VWF levels. A pedigree linkage analysis was first performed in five extended French-Canadian families, including 253 individuals, to identify genomic regions linked to FVIII or VWF levels. Identified regions were further explored using 'in silico' genome-wide association studies (GWAS) data on VTE (419 patients and 1228 controls), and two independent case-control studies (MARTHA and FARIVE) for VTE, gathering 1166 early-onset patients and 1408 healthy individuals. Single nucleotide polymorphisms (SNPs) associated with VTE risk were further investigated in relation to plasma levels of FVIII and VWF in a cohort of 108 healthy nuclear families. Four main linkage regions were identified, among which the well-characterized ABO locus, the recently identified STAB 2 gene, and a third one, on chromosome 6q13-14, harbouring four non-redundant SNPs, associated with VTE at P < 10(-4) in the GWAS dataset. The association of one of these SNPs, rs9363864, with VTE was further replicated in the MARTHA and FARIVE studies. The rs9363864-AA genotype was associated with a lower risk for VTE (OR = 0.58 [0.42-0.80], P = 0.0005) but mainly in non-carriers of the FV Leiden mutation. This genotype was further found to be associated with the lowest levels of FVIII (P = 0.006) and VWF (P = 0.001). The BAI3 locus where the rs9363864 maps is a new candidate for VTE risk.