Gene variants associated with deep vein thrombosis

F5 6665A>G Polymorphism Is Associated with Increased Risk of Venous Thromboembolism in Females

The main goal of our study was to assess the potential effect of the polymorphism of the coagulation-related genes F2, F5, and F13A on the risk of venous thromboembolism (VTE) development. The study was conducted at the Clinical Center, Podgorica, Montenegro, and included 103 VTE patients and 106 sex- and age-matched healthy controls. Demographic, clinical, and laboratory data were obtained from the medical records and questionnaires. Genotyping for F2 19911A>G (rs3136516), F5 6665A>G (rs6027), and F13A 102G>T (rs5985) was performed by allele-specific PCR. Controlling for the effect of known risk factors, the presence of at least one variant F5 6665 G allele conferred a significantly higher risk of VTE among females [OR (95%CI): 64.06 (5.38; 763.61)], but not among males. In addition, thromboembolic events were associated with comorbidities [OR (95%CI): 197.10 (19.17; 2026.19)], overweight [OR (95%CI): 33.59 (2.47; 456.65)], and the presence of F2 20210G>A [OR (95%CI): 32.43 (4.21; 249.77)] and F5 1601G>A [OR (95%CI): 144.80 (13.59; 1542.63)] in females, as well as with comorbidities [OR (95%CI): 6.32 (1.90; 20.98)], family history of VTE [OR (95%CI): 8.10 (2.28; 28.83)], and the presence of F5 1601G>A [OR (95%CI): 20.10 (2.34; 173.02)] in males. Our study reports an association between the presence of at least one F5 6665G variant allele and an increased risk of VTE development in females. Our results indicate that F5 6665A>G, in combination with other confirmed factors of influence, such as comorbidities, overweight, F2 20210G>A, and F5 1601G>A, could contribute to VTE risk prediction in females.

Association between epidermal growth factor receptor-tyrosine kinase inhibitors and venous thromboembolism among older patients with advanced non-small cell lung cancer

BACKGROUND

Venous thromboembolism (VTE) risk is higher among patients with non-small cell lung cancer (NSCLC) and specific subgroups, including the elderly, but little is known about the VTE risk of different generations of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and whether the risk differs by demographic characteristics. This study aims to compare the risk of VTE (deep venous thromboembolism [DVT]; pulmonary embolism [PE]) between a third-generation EGFR-TKI and first/second-generation EGFR-TKIs and stratify VTE risk by sex, age, and race/ethnicity in third-generation EGFR-TKI users.

METHODS

Via the 2006-2019 Surveillance, Epidemiology, and End Results-Medicare database, this retrospective cohort study included older patients (aged ≥65 years) with advanced NSCLC who initiated on a third-generation EGFR-TKI (n = 493) and first/second-generation EGFR-TKIs (n = 1036). We estimated the hazard ratio (HR) and its 95% confidence interval (95% CI) with the Cox proportional hazards model.

RESULTS

A third-generation EGFR-TKI had a significantly higher VTE risk than first/second-generation EGFR-TKIs (HR, 1.26 [95% CI, 1.01-1.57]; p = .037), with an elevated risk in males (HR, 2.16 [95% CI, 1.47-3.19]; p < .001), patients aged ≥75 years (HR, 1.38 [95% CI, 1.04-1.83]; p = .026), and non-Hispanic Whites (HR, 1.46 [95% CI, 1.10-1.95]; p = .010). Males consistently showed a significantly higher risk of DVT (HR, 2.49 [95% CI, 1.29-4.80]; p = .007) and PE (HR, 2.00 [95% CI, 1.29-3.11]; p = .002). A significantly higher risk of DVT (HR, 1.54 [95% CI, 1.00-2.37]; p = .050) and PE (HR, 1.47 [95% CI, 1.06-2.05]; p = .021) was shown in patients aged ≥75 years and non-Hispanic Whites, respectively. Among third-generation EGFR-TKI users, non-Hispanic Whites had a significantly higher risk of VTE (HR, 2.04 [95% CI, 1.03-4.02]; p = .041) and PE (HR, 2.88 [95% CI, 1.24-6.70]; p = .014) than non-Hispanic Asian/Pacific Islanders.

CONCLUSIONS

Close monitoring of VTE events in high-risk patients is essential to promote early diagnosis and treatment.

Bietti's crystalline dystrophy: genotyping and deep qualitative and quantitative phenotyping in preparation for clinical trials

PURPOSE

To qualitatively and quantitatively characterise the genotypes and phenotypes of Bietti's crystalline dystrophy (BCD) in a cohort of patients.

DESIGN

Cross-sectional and observational study.

METHODS

Clinically confirmed BCD patients were recruited for genotyping and phenotyping. Multiple retinal imaging modalities were employed. Atrophy in the fovea was adopted as major consideration for staging strategy, while percentage area of autofluorescence (AF) atrophy (PAFA) in the macula was determined for quantitation.

RESULTS

In 74 clinically diagnosed BCD patients, c.802-8_810del17insGC was shown the predominant variant of the CYP4V2 gene (allele frequency 55.4%). Sixty-two cases (123 eyes) with full imaging data were classified according to a modified criterion into stages 1 (n=8, 6.50%), 2A (n=9, 7.32%), 2B (n=17, 13.82%), 3A (n=30, 24.39%) and 3B (n=59, 47.97%). The eyes of the stage 2B were particularly deemed 'high risk' due to atrophy near fovea, while in stage 3A, though with remarkable foveal atrophy, preserved retinal pigment epithelium/photoreceptor islands near the fovea were found in 14 eyes. A tendency of increase in PAFA with age was found (rs=0.31, p=0.014). Significant PAFA increase was shown through stages 1 to 3B, and best-corrected visual acuity (BCVA, Logarithm of the Minimum Angle of Resolution) was shown to moderately correlate with PAFA (rs=0.56, p<0.001).

CONCLUSION

The PAFA might be an efficient biomarker for BCD severities correlating with BCVA. The highly heterogeneous chorioretinopathy and BCVA of BCD cases appear to be associated with disease stages, progression types and patients' ages. Foveal involvement should be of a major concern for consideration of potential therapeutic intervention.

Targeting factor XI and factor XIa to prevent thrombosis

ABSTRACT

Direct oral anticoagulants (DOACs) that inhibit the coagulation proteases thrombin or factor Xa (FXa) have replaced warfarin and other vitamin K antagonists (VKAs) for most indications requiring long-term anticoagulation. In many clinical situations, DOACs are as effective as VKAs, cause less bleeding, and do not require laboratory monitoring. However, because DOACs target proteases that are required for hemostasis, their use increases the risk of serious bleeding. Concerns over therapy-related bleeding undoubtedly contribute to undertreatment of many patients who would benefit from anticoagulation therapy. There is considerable interest in the plasma zymogen factor XI (FXI) and its protease form factor XIa (FXIa) as drug targets for treating and preventing thrombosis. Laboratory and epidemiologic studies support the conclusion that FXI contributes to venous and arterial thrombosis. Based on 70 years of clinical observations of patients lacking FXI, it is anticipated that drugs targeting this protein will cause less severe bleeding than warfarin or DOACs. In phase 2 studies, drugs that inhibit FXI or FXIa prevent venous thromboembolism after total knee arthroplasty as well as, or better than, low molecular weight heparin. Patients with heart disease on FXI or FXIa inhibitors experienced less bleeding than patients taking DOACs. Based on these early results, phase 3 trials have been initiated that compare drugs targeting FXI and FXIa to standard treatments or placebo. Here, we review the contributions of FXI to normal and abnormal coagulation and discuss results from preclinical, nonclinical, and clinical studies of FXI and FXIa inhibitors.

The incidence of the thrombophilic SNPs rs6025, rs1799963, rs2066865, rs2289252, and rs8176719 in chronic thromboembolic pulmonary hypertension

INTRODUCTION

Chronic thromboembolic pulmonary hypertension (CTEPH) and venous thromboembolism (VTE) are thought to share many common risk factors. Our study aimed to determine the frequencies of 5 thrombosis-related gene single nucleotide polymorphisms (SNPs) associated with VTE in patients with CTEPH (n 129) compared with a control group of healthy individuals without a history of VTE (n 2637).

METHODS

The SNPs of the following genes were investigated: F5 (F V Leiden, rs6025), F2 prothrombin (rs1799963), fibrinogen gamma (FGG, rs2066865), F11 (rs2289252) and ABO (non-O, rs8176719) in both groups.

RESULTS

The study found that the rs1799963 variant was more common in patients with chronic thromboembolic pulmonary hypertension (CTEPH) compared to the control group (p < .0001). The GA heterozygous variant showed a significant increase with an odds ratio (OR) of 4.480 (95% CI: 2.344-8.562) or a finding by maximum likelihood analysis (MLA) with p < .0001. Additionally, there was a notable increase in the rs8176719 variant with p < .0001 in CTEPH patients. Both the homozygous G/G variant and the heterozygous -/G variant also showed an increase, with OR of 4.2317 (95% CI: 2.45571-7.2919) and 2.4324 (95% CI: 1.46435-4.0403) respectively, or MLA (p < .0001 and p .0006). The study also revealed a higher prevalence of the heterozygous C/T variant of rs2289252 in CTEPH patients, with an OR of 1.5543 (95% CI: 1.02503-2.3568) or MLA (p .0379).

CONCLUSION

The study suggests that the observed gene polymorphisms F2 (rs1799963), ABO (rs8176719), and F11 (rs2289252) may play a role as independent heritable risk factors in the development of CTEPH.

Factor V variants in bleeding and thrombosis

A state-of-the-art lecture titled "Factor V variants in bleeding and thrombosis" was presented at the International Society on Thrombosis and Haemostasis (ISTH) congress in 2023. Blood coagulation is a finely regulated cascade of enzymatic reactions culminating in thrombin formation and fibrin deposition at the site of injury. Factor V (FV) plays a central role in this process, as its activated form is an essential procoagulant cofactor in prothrombin activation. However, other molecular forms of FV act as anticoagulant cofactors of activated protein C and tissue factor pathway inhibitor α, respectively, thereby contributing to the regulation of coagulation. This dual procoagulant and anticoagulant character makes FV a central regulator of the hemostatic balance, and quantitative and qualitative alterations of FV may be associated with an increased risk of bleeding or venous thrombosis. Here, we review the procoagulant and anticoagulant functions of FV and the manifold mechanisms by which F5 gene mutations may affect the balance between these opposite functions and thereby predispose individuals to bleeding or venous thrombosis. In particular, we discuss our current understanding of the 3 main pathological conditions related to FV, namely FV deficiency, activated protein C resistance, and the overexpression of FV-short, a minor splicing isoform of FV with tissue factor pathway inhibitor α-dependent anticoagulant properties and an emerging role as a key regulator of the initiation of coagulation. Finally, we summarize relevant new data on this topic presented during the 2023 ISTH Congress.

CYP4V2 rs56413992 C > T was associated with the risk of coronary heart disease in the Chinese Han population: a case-control study

PURPOSE

The research aimed to detect the association between single nucleotide polymorphisms (SNPs) in CYP4V2 gene and coronary heart disease (CHD) risk.

METHODS

This case-control study included 487 CHD subjects and 487 healthy individuals. Logistic regression was performed to analyze the connection between five SNPs in CYP4V2 (rs1398007, rs13146272, rs3736455, rs1053094, and rs56413992) and CHD risk, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the connection.

RESULTS

As a result, we found that rs56413992 T allele (OR = 1.36, 95% CI = 1.09-1.70, p = 0.007) and CT genotype (OR = 1.40, 95% CI = 1.06-1.83, p = 0.017) were significantly associated with an increased risk of CHD in the overall analysis. Precisely, rs56413992 was linked to an elevated risk of CHD in people aged > 60, males, smokers and drinkers. The study also indicated that rs1398007 was linked to an increased CHD risk in drinkers. In addition, rs1053094 was correlated with a decreased risk of CHD complicated with diabetes mellitus (DM), and rs1398007 was correlated with a decreased risk of CHD complicated with hypertension (HTN).

CONCLUSION

This study was the first to experimentally demonstrate that CYP4V2 rs56413992 was associated with the risk of CHD, which will provide a certain reference for revealing the pathogenesis of CHD.

Genomic science of risk prediction for venous thromboembolic disease: convenient clarification or compounding complexity

Venous thromboembolism (VTE) refers to abnormal blood clots in veins occurring in 1 to 2 per 1000 individuals every year. While anticoagulant treatment can prevent VTE, it increases the risk of bleeding. This emphasizes the importance of identifying individuals with a high risk of VTE and providing prophylactic interventions to these individuals to reduce both VTE and bleeding risks. Current risk assessment of VTE is based on the combination of mainly clinical risk factors. With the identification of an increasing number of genetic variants associated with the risk of VTE, the addition of genetic findings to clinical prediction models can improve risk prediction for VTE. Especially for individuals in high-risk situations, the added value of genetic findings to clinical prediction models may have benefits such as better prophylaxis of VTE and the reduced side effects of bleeding from unnecessary treatment. Nevertheless, the question of whether these models will eventually have clinical utility remains to be proven. Here, we review the current state of knowledge on genetic risk factors for VTE, explore genetic prediction models for VTE, and discuss their clinical implications and challenges.

Thrombogenesis-associated genetic determinants as predictors of thromboembolism and prognosis in cervical cancer

Venous thromboembolism (VTE) is a leading cause of death among cancer patients. Khorana score (KS) is the most studied tool to predict cancer-related VTE, however, it exerts poor sensitivity. Several single-nucleotide polymorphisms (SNPs) have been associated with VTE risk in the general population, but whether they are predictors of cancer-related VTE is a matter of discussion. Compared to other solid tumours, little is known about VTE in the setting of cervical cancer (CC) and whether thrombogenesis-related polymorphisms could be valuable biomarkers in patients with this neoplasia. This study aims to analyse the effect of VTE occurrence on the prognosis of CC patients, explore the predictive capability of KS and the impact of thrombogenesis-related polymorphisms on CC-related VTE incidence and patients' prognosis regardless of VTE. A profile of eight SNPs was evaluated. A retrospective hospital-based cohort study was conducted with 400 CC patients under chemoradiotherapy. SNP genotyping was carried on by using TaqMan® Allelic Discrimination methodology. Time to VTE occurrence and overall survival were the two measures of clinical outcome evaluated. The results indicated that VTE occurrence (8.5%) had a significant impact on the patient's survival (log-rank test, P < 0.001). KS showed poor performance (KS ≥ 3, χ², P = 0.191). PROCR rs10747514 and RGS7 rs2502448 were significantly associated with the risk of CC-related VTE development (P = 0.021 and P = 0.006, respectively) and represented valuable prognostic biomarkers regardless of VTE (P = 0.004 and P = 0.010, respectively). Thus, thrombogenesis-related genetic polymorphisms may constitute valuable biomarkers among CC patients allowing a more personalized clinical intervention.

Whole Genome Analysis of Venous Thromboembolism: the Trans-Omics for Precision Medicine Program

BACKGROUND

Risk for venous thromboembolism has a strong genetic component. Whole genome sequencing from the TOPMed program (Trans-Omics for Precision Medicine) allowed us to look for new associations, particularly rare variants missed by standard genome-wide association studies.

METHODS

The 3793 cases and 7834 controls (11.6% of cases were individuals of African, Hispanic/Latino, or Asian ancestry) were analyzed using a single variant approach and an aggregate gene-based approach using our primary filter (included only loss-of-function and missense variants predicted to be deleterious) and our secondary filter (included all missense variants).

RESULTS

Single variant analyses identified associations at 5 known loci. Aggregate gene-based analyses identified only PROC (odds ratio, 6.2 for carriers of rare variants; P=7.4×10-14) when using our primary filter. Employing our secondary variant filter led to a smaller effect size at PROC (odds ratio, 3.8; P=1.6×10-14), while excluding variants found only in rare isoforms led to a larger one (odds ratio, 7.5). Different filtering strategies improved the signal for 2 other known genes: PROS1 became significant (minimum P=1.8×10-6 with the secondary filter), while SERPINC1 did not (minimum P=4.4×10-5 with minor allele frequency <0.0005). Results were largely the same when restricting the analyses to include only unprovoked cases; however, one novel gene, MS4A1, became significant (P=4.4×10-7 using all missense variants with minor allele frequency <0.0005).

CONCLUSIONS

Here, we have demonstrated the importance of using multiple variant filtering strategies, as we detected additional genes when filtering variants based on their predicted deleteriousness, frequency, and presence on the most expressed isoforms. Our primary analyses did not identify new candidate loci; thus larger follow-up studies are needed to replicate the novel MS4A1 locus and to identify additional rare variation associated with venous thromboembolism.

The Risk Factors for New-Onset Calf Muscle Venous Thrombosis after Hip Fracture Surgery

BACKGROUND

Calf muscle venous thrombosis (CMVT) is among the most important medical complications after hip surgery. CMVT has been known for many years, but many opinions about the incidence and risk factors of CMVT are still controversial. The objective of this retrospective study was to investigate the incidence and associated risk factors of postoperative CMVT in patients with hip fractures.

METHODS

Patients with hip fractures from January 2020 to April 2022 (n = 320) at Shenzhen Second People's Hospital were recruited in this study. The personal characteristics and clinical data of CMVT and no-CMVT patients were compared and analyzed. Binary logistic regression analyses were performed to identify potential risk factors of CMVT in patients with hip fractures. Finally we performed a receiver operating characteristic (ROC) curve analysis to compare the diagnostic values of different variables.

RESULTS

The overall incidence of new-onset CMVT in patients with hip fractures was 18.75% (60 of 320). Among the 60 CMVT patients, 70% (42 of 60) were diagnosed with femoral neck fractures, 28.3% (17 of 60) with intertrochanteric fractures, and 1.7% (1 of 60) with subtrochanteric fractures. No pulmonary embolism (PE) occurred. High preoperative D-dimer (OR = 1.002, 95%CI 0.97-1.03), sex (OR = 1.22, 95%CI 0.51-2.96), the caprini score (OR = 2.32, 95%CI 1.05-5.16) and the waterlow score (OR = 1.077, 95%CI 0.35-3.36) significantly increased the risk of developing postoperative new-onset CMVT.

CONCLUSIONS

CMVT has become a common clinical disease, and its harm should not be underestimated. Our study found that D-dimer, sex, the caprini score and the waterlow score were independent risk factors for postoperative CMVT. According to our clinical work, we should pay attention to identifying the risk factors of CMVT formation and targeted intervention measures to prevent new-onset CMVT.

Inherited antithrombin deficiency caused by a mutation in the SERPINC1 gene: A case report

RATIONALE

Inherited antithrombin deficiency (ATD) is a major cause of thrombotic deficiency. Genetic testing is of great value in the diagnosis of hereditary thrombophilia. Herein, we report a case of inherited ATD admitted to our hospital. We include the results of genealogy and discuss the significance of genetic testing in high-risk groups of hereditary thrombophilia.

PATIENT CONCERNS

A 16-year-old male patient presented with chest tightness, shortness of breath, wheezing, and intermittent fever (up to 39 °C) after strenuous exercise for 2 weeks. He also had a cough with white sputum with a small amount of bright red blood in the sputum and occasional back pain.

DIAGNOSES

The blood tests showed that the patient's antithrombin III concentration and activity were both significantly reduced to 41% and 43.2%, respectively. Enhanced chest computed tomography scans showed pulmonary infarction in the lower lobe of the right lung with multiple embolisms in the bilateral pulmonary arteries and branches. Lower vein angiography revealed a contrast-filling defect of the inferior vena cava and left common iliac vein. Thrombosis was considered as a differential diagnosis. His father and his uncle also had a history of thrombosis. The patient was diagnosed with inherited ATD. Further, peripheral venous blood samples of the family members were collected for whole-exome gene sequencing, and Sanger sequencing was used to verify the gene mutation site in the family. The patient and his father had a SERPINC1 gene duplication mutation: c.1315_1345dupCCTTTCCTGGTTTTTAAGAGAAGTTCCTC (NM000488.4).

INTERVENTIONS

An inferior vena cava filter was inserted to avoid thrombus shedding from the lower limbs. Urokinase was injected intermittently through the femoral vein cannula for thrombolysis. Heparin combined with warfarin anticoagulant therapy was sequentially administered. After reaching the international normalized ratio, heparin was discontinued, and oral warfarin anticoagulant therapy was continued. After discharge, the patient was switched to rivaroxaban as oral anticoagulation therapy.

OUTCOMES

The patient's clinical symptoms disappeared. reexamination showed that the thrombotic load was less than before, and the inferior vena cava filter was then removed.

LESSONS

By this report we highlight that gene detection and phenotypic analysis are important means to study inherited ATD.

Cross-Ancestry Investigation of Venous Thromboembolism Genomic Predictors

BACKGROUND

Venous thromboembolism (VTE) is a life-threatening vascular event with environmental and genetic determinants. Recent VTE genome-wide association studies (GWAS) meta-analyses involved nearly 30 000 VTE cases and identified up to 40 genetic loci associated with VTE risk, including loci not previously suspected to play a role in hemostasis. The aim of our research was to expand discovery of new genetic loci associated with VTE by using cross-ancestry genomic resources.

METHODS

We present new cross-ancestry meta-analyzed GWAS results involving up to 81 669 VTE cases from 30 studies, with replication of novel loci in independent populations and loci characterization through in silico genomic interrogations.

RESULTS

In our genetic discovery effort that included 55 330 participants with VTE (47 822 European, 6320 African, and 1188 Hispanic ancestry), we identified 48 novel associations, of which 34 were replicated after correction for multiple testing. In our combined discovery-replication analysis (81 669 VTE participants) and ancestry-stratified meta-analyses (European, African, and Hispanic), we identified another 44 novel associations, which are new candidate VTE-associated loci requiring replication. In total, across all GWAS meta-analyses, we identified 135 independent genomic loci significantly associated with VTE risk. A genetic risk score of the significantly associated loci in Europeans identified a 6-fold increase in risk for those in the top 1% of scores compared with those with average scores. We also identified 31 novel transcript associations in transcriptome-wide association studies and 8 novel candidate genes with protein quantitative-trait locus Mendelian randomization analyses. In silico interrogations of hemostasis and hematology traits and a large phenome-wide association analysis of the 135 GWAS loci provided insights to biological pathways contributing to VTE, with some loci contributing to VTE through well-characterized coagulation pathways and others providing new data on the role of hematology traits, particularly platelet function. Many of the replicated loci are outside of known or currently hypothesized pathways to thrombosis.

CONCLUSIONS

Our cross-ancestry GWAS meta-analyses identified new loci associated with VTE. These findings highlight new pathways to thrombosis and provide novel molecules that may be useful in the development of improved antithrombosis treatments.

Transmembrane protease serine 2 (TMPRSS2) rs75603675, comorbidity, and sex are the primary predictors of COVID-19 severity

By the end of December 2021, coronavirus disease 2019 (COVID-19) produced more than 271 million cases and 5.3 million deaths. Although vaccination is an effective strategy for pandemic control, it is not yet equally available in all countries. Therefore, identification of prognostic biomarkers remains crucial to manage COVID-19 patients. The aim of this study was to evaluate predictors of COVID-19 severity previously proposed. Clinical and demographic characteristics and 120 single-nucleotide polymorphisms were analyzed from 817 patients with COVID-19, who attended the emergency department of the Hospital Universitario de La Princesa during March and April 2020. The main outcome was a modified version of the 7-point World Health Organization (WHO) COVID-19 severity scale (WHOCS); both in the moment of the first hospital examination (WHOCS-1) and of the severest WHOCS score (WHOCS-2). The TMPRSS2 rs75603675 genotype (OR = 0.586), dyslipidemia (OR = 2.289), sex (OR = 0.586), and the Charlson Comorbidity Index (OR = 1.126) were identified as the main predictors of disease severity. Consequently, these variables might influence COVID-19 severity and could be used as predictors of disease development.

Impact of hereditary thrombophilia on cancer-associated thrombosis, tumour susceptibility and progression: A review of existing evidence

Venous thromboembolism (VTE) is a cardiovascular disorder frequently diagnosed among cancer patients. Aside from being common, VTE severely deteriorates the prognosis of these patients as they face a higher risk of morbidity and mortality, which makes clinical tools able to identify the patients more prompt to thrombogenesis very attractive. Over the years, several genetic polymorphisms have been linked with VTE susceptibility in the general population. However, their clinical usefulness as predictive biomarkers for cancer-related VTE is yet unclear. Furthermore, as a two-way association between cancer and VTE is well-recognized, with haemostatic components fuelling tumour progression, haemostatic gene polymorphisms constitute potential cancer predictive and/or prognostic biomarkers as well. Thus, in this article, we review the existing evidence on the role of these polymorphisms on cancer-related VTE and their impact on cancer onset and progression. Despite the promising findings, the existing studies had inconsistent results most likely due to their limited statistical power and population heterogeneity. Future studies are therefore required to clarify the role of these polymorphisms in setting of malignancy.

Identifying causal genes for stroke via integrating the proteome and transcriptome from brain and blood

Background

Genome-wide association studies (GWAS) have revealed numerous loci associated with stroke. However, the underlying mechanisms at these loci in the pathogenesis of stroke and effective stroke drug targets are elusive. Therefore, we aimed to identify causal genes in the pathogenesis of stroke and its subtypes.

Methods

Utilizing multidimensional high-throughput data generated, we integrated proteome-wide association study (PWAS), transcriptome-wide association study (TWAS), Mendelian randomization (MR), and Bayesian colocalization analysis to prioritize genes that contribute to stroke and its subtypes risk via affecting their expression and protein abundance in brain and blood.

Results

Our integrative analysis revealed that ICA1L was associated with small-vessel stroke (SVS), according to robust evidence at both protein and transcriptional levels based on brain-derived data. We also identified NBEAL1 that was causally related to SVS via its cis-regulated brain expression level. In blood, we identified 5 genes (MMP12, SCARF1, ABO, F11, and CKAP2) that had causal relationships with stroke and stroke subtypes.

Conclusions

Together, via using an integrative analysis to deal with multidimensional data, we prioritized causal genes in the pathogenesis of SVS, which offered hints for future biological and therapeutic studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03377-9.

Patients with SERPINC1 rs2227589 polymorphism found to have multiple cerebral venous sinus thromboses despite a normal antithrombin level: A case report

BACKGROUND

The hereditary antithrombin (AT) deficiency caused by SERPINC1 gene mutation is an autosomal dominant thrombotic disorder. An increasing number of studies have shown that mutations in the SERPINC1 rs2227589 polymorphic site are correlated with a risk of venous thromboembolism (VTE) at common sites, such as lower extremity deep venous thrombosis and pulmonary thromboembolism. Currently, there are no reports of cerebral venous sinus thrombosis (CVST), a VTE site with a low incidence rate and rs2227589 polymorphism.

CASE SUMMARY

Here, we report a Chinese CVST case with a mutation of the SERPINC1 rs2227589 polymorphic site, which did not cause significant AT deficiency. In a 50-year-old male patient presenting with multiple cerebral venous sinus thromboses no predisposing factors were detected, although a relative had a history of lower extremity deep venous thrombosis. We performed sequencing of the SERPINC1 gene for the patient and his daughter, which revealed the same heterozygous mutation at the rs2227589 polymorphic site: c.41+141G>A.

CONCLUSION

The results showed that more studies should be conducted to assess the correlation between rs2227589 polymorphism and CVST.

Today's view of hereditary thrombophilia

Venous thromboembolism (VTE) is still a serious medical problem with the non-decreasing incidence of new cases despite prophylaxis in risky situations. It is a multifactorial disease, in which the hereditary component is also significantly involved. The aim of the current research is to search for new polymorphisms that are involved in thrombogenesis in addition to classical thrombophilia (deficiency of natural coagulation inhibitors and FVL and FII prothrombin mutations). The article provides an overview of the results of already performed genome-wide association studies of VTE and their use for the calculation of the so-called polygenic risk score, which could be used for individualized prevention of VTE after standardization of the method.

Kallikrein augments the anticoagulant function of the protein C system in thrombin generation

BACKGROUND

Genetics play a significant role in coagulation phenotype and venous thromboembolism risk. Resistance to the anticoagulant activated protein C (APC) is an established risk for thrombosis. Herein, we explored the genetic determinants of thrombin generation (TG) and thrombomodulin (TM)-modulated TG using plasma from the Human Functional Genomics Project.

METHODS

Calibrated TG was measured both in absence and presence of TM using tissue factor as trigger. Genetic determinants of TG parameters and protein C pathway function were assessed using genome-wide single-nucleotide polymorphism (SNP) genotyping. Plasma samples were supplemented with purified apolipoprotein A-IV, prekallikrein, or kallikrein to test their influence on the anticoagulant function of TM and APC in TG.

RESULTS

Thrombin generation data from 392 individuals were analyzed. Genotyping showed that the KLKB1 gene (top SNP: rs4241819) on chromosome 4 was associated with the normalized sensitivity ratio of endogenous thrombin potential to TM at genome-wide level (nETP-TMsr, P = 4.27 × 10-8 ). In vitro supplementation of kallikrein, but not prekallikrein or apolipoprotein A-IV, into plasma dose-dependently augmented the anticoagulant effect of TM and APC in TG. Variations of rs4241819 was not associated with the plasma concentration of prekallikrein. Association between rs4241819 and nETP-TMsr was absent when TG was measured in presence of a contact pathway inhibitor corn trypsin inhibitor.

CONCLUSIONS

Our results suggest that kallikrein plays a role in the regulation of the anticoagulant protein C pathway in TG, which may provide a novel mechanism for the previously observed association between the KLKB1 gene and venous thrombosis.

RETINAL AND CHOROIDAL BLOOD PERFUSION IN PATIENTS WITH BIETTI CRYSTALLINE DYSTROPHY

PURPOSE

To compare changes of chorioretinal blood perfusion between Bietti crystalline dystrophy (BCD) and typical retinitis pigmentosa and perform a staging and a longitudinal analysis of chorioretinal perfusion in BCD.

METHODS

Twenty-eight patients with BCD (56 eyes), 28 patients with typical retinitis pigmentosa (56 eyes), and 28 healthy subjects (56 eyes) were enrolled. Macular structural parameters and subfoveal choroidal thickness were measured using optical coherence tomography. Retinal vessel and perfusion densities were calculated using optical coherence tomography angiography. Choroidal blood perfusion was assessed through indocyanine green angiography. The results of the BCD group were compared with those of the retinitis pigmentosa and control groups and followed by a staging and a longitudinal analysis of BCD.

RESULTS

Macular structural and perfusion parameters were decreased less in the BCD group than those in the retinitis pigmentosa group. Subfoveal choroidal thickness was significantly thinner in the BCD group, with a remarkable choroidal perfusion deficit using indocyanine green angiography. The staging analysis revealed damage of both retinal and choroidal perfusion in BCD; however, the longitudinal analysis showed the impairment of choroidal perfusion outweighed retinal.

CONCLUSION

Both retinal and choroidal blood perfusion are impaired in BCD, but choroidal perfusion deficit caused by CYP4V2 mutations may play a more vital pathologic role.

Cryptogenic Stroke in the Young: Role of Candidate Gene Polymorphisms in Indian Patients with Ischemic Etiology

CONTEXT

Strokes that remain without a definite cause even after an extensive workup, termed cryptogenic strokes, constitute up to 30-40% of ischemic strokes (ISs) in the young. Some of them can have a genetic basis. However, the well-established genetic causes account for only a small percentage of these cases.

AIM

To evaluate the association of cryptogenic young IS with 16 candidate gene polymorphisms.

SETTINGS AND DESIGN

A case-control study with cryptogenic young IS patients (South and North Indians; n = 105) and age, sex, and ethnicity-matched controls (n = 215).

SUBJECTS AND METHODS

Genotyping was carried out by PCR-RFLP method using DNA extracted from the blood.

STATISTICAL ANALYSIS USED

Association of the genotypes with the disease was studied using Chi-square test.

RESULTS

MTHFR rs1801133 and KNG1 rs710446 showed significant statistical association with cryptogenic young IS (P = 0.0261 and 0.0157, respectively) in the Indian population. Significant association of KNG1 rs710446 (P 0.0036) and FXII rs1801020 (P 0.0376) with cryptogenic young stroke in South Indian males, SERPINC1 rs2227589 in South Indian female patients (P = 0.0374), and CYP4V2 rs13146272 in North Indian males (P = 0.0293) was observed.

CONCLUSIONS

Our study indicates that in the Indian population MTHFR rs1801133, KNG rs710446, FXII rs1801020, SERPINC1 rs2227589, CYP4V2 rs13146272, and FXIII V34L may be significant risk factors for cryptogenic IS in the young. In addition, ethnicity and gender play a significant role. Further studies with larger sample size are required to completely establish these polymorphisms as risk factors for cryptogenic IS in young Indians.

Platelet GPVI (Glycoprotein VI) and Thrombotic Complications in the Venous System

The immunoglobulin receptor GPVI (glycoprotein VI) is selectively expressed on megakaryocytes and platelets and is currently recognized as a receptor for not only collagen but also a variety of plasma and vascular proteins, including fibrin, fibrinogen, laminin, fibronectin, and galectin-3. Deficiency of GPVI is protective in mouse models of experimental thrombosis, pulmonary thromboembolism as well as in thromboinflammation, suggesting a role of GPVI in arterial and venous thrombus formation. In humans, platelet GPVI deficiency is associated with a mild bleeding phenotype, whereas a common variant rs1613662 in the GP6 gene is considered a risk factor for venous thromboembolism. However, preclinical studies on the inhibition of GPVI-ligand interactions are focused on arterial thrombotic complications. In this review we discuss the emerging evidence for GPVI in venous thrombus formation and leukocyte-dependent thromboinflammation, extending to venous thromboembolism, pulmonary thromboembolism, and cancer metastasis. We also recapitulate indications for circulating soluble GPVI as a biomarker of thrombosis-related complications. Collectively, we conclude that the current evidence suggests that platelet GPVI is also a suitable cotarget in the prevention of venous thrombosis due to its role in thrombus consolidation and platelet-leukocyte complex formation.

Gene Variants Associated With Venous Thrombosis: A Replication Study in a Brazilian Multicentre Study

Single nucleotide polymorphisms (SNP) associated with Venous Thromboembolism (VTE) risk have been identified in European and American populations. Replicate SNPs associated with VTE in a Brazilian multicenter case-control study of the Southeast region. Patients with previous VTE assisted at the Outpatient Clinics of 3 centers of the Southeast Brazilian region were compared to normal controls of the same geographic region. We evaluated 29 SNPs associated with VTE risk in other populations, and 90 SNPs for stratification analysis of the population. Due to high admixture of Brazilian population and lack of previous studies, the calculation of the sample power was performed after genotyping. Sample size, allelic frequency and Hardy-Weinberg equilibrium were estimated. The association and odds ratio analyses were estimated by logistic regression and the results were adjusted for multiple tests using Bonferroni correction. The evaluation of the genetic structure similarity in the cases and controls was performed by AMOVA. 436 cases and 430 controls were included. It was demonstrated that this sample has a statistical power to detect a genetic association of 79.4%. AMOVA showed that the genetic variability between groups was 0.0% and 100% within each group. None of the SNPs showed association with VTE in our population. A Brazilian multicenter case-control study with adequate sample power, high genetic variability though no stratification between groups, showed no replication of SNPs associated with VTE. The high admixture of Brazilian population may be responsible for these results, emphasizing the influence of the population genetic structure in association studies.

Epidemiology and Genetics of Venous Thromboembolism and Chronic Venous Disease

Venous disease is a term that broadly covers both venous thromboembolic disease and chronic venous disease. The basic pathophysiology of venous thromboembolism and chronic venous disease differ as venous thromboembolism results from an imbalance of hemostasis and thrombosis while chronic venous disease occurs in the setting of tissue damage because of prolonged venous hypertension. Both diseases are common and account for significant mortality and morbidity, respectively, and collectively make up a large health care burden. Despite both diseases having well-characterized environmental components, it has been known for decades that family history is an important risk factor, implicating a genetic element to a patient's risk. Our understanding of the pathogenesis of these diseases has greatly benefited from an expansion of population genetic studies from pioneering familial studies to large genome-wide association studies; we now have multiple risk loci for each venous disease. In this review, we will highlight the current state of knowledge on the epidemiology and genetics of venous thromboembolism and chronic venous disease and directions for future research.

Activated protein C has a regulatory role in factor VIII function

Mechanisms thought to regulate activated factor VIII (FVIIIa) cofactor function include A2-domain dissociation and activated protein C (APC) cleavage. Unlike A2-domain dissociation, there is no known phenotype associated with altered APC cleavage of FVIII, and biochemical studies have suggested APC plays a marginal role in FVIIIa regulation. However, the in vivo contribution of FVIIIa inactivation by APC is unexplored. Here we compared wild-type B-domainless FVIII (FVIII-WT) recombinant protein with an APC-resistant FVIII variant (FVIII-R336Q/R562Q; FVIII-QQ). FVIII-QQ demonstrated expected APC resistance without other changes in procoagulant function or A2-domain dissociation. In plasma-based studies, FVIII-WT/FVIIIa-WT demonstrated dose-dependent sensitivity to APC with or without protein S, whereas FVIII-QQ/FVIIIa-QQ did not. Importantly, FVIII-QQ demonstrated approximately fivefold increased procoagulant function relative to FVIII-WT in the tail clip and ferric chloride injury models in hemophilia A (HA) mice. To minimize the contribution of FV inactivation by APC in vivo, a tail clip assay was performed in homozygous HA/FV Leiden (FVL) mice infused with FVIII-QQ or FVIII-WT in the presence or absence of monoclonal antibody 1609, an antibody that blocks murine PC/APC hemostatic function. FVIII-QQ again demonstrated enhanced hemostatic function in HA/FVL mice; however, FVIII-QQ and FVIII-WT performed analogously in the presence of the PC/APC inhibitory antibody, indicating the increased hemostatic effect of FVIII-QQ was APC specific. Our data demonstrate APC contributes to the in vivo regulation of FVIIIa, which has the potential to be exploited to develop novel HA therapeutics.

Prevalence of thrombophilia-associated genetic risk factors in blood donors of a regional hospital in southern Brazil

Introduction

Thromboembolic events occur due to an imbalance in the hemostasis and some factors associated with this condition can be inherited. In order to evaluate the frequency of genotypes considered to be common hereditary risk factors for thrombophilia associated with venous thrombosis (g.1691G > A and g.20210G > A) and hyperhomocysteinemia (g.677C > T and g.1298A > C), samples from voluntary healthy blood donors at the Hospital de Clínicas de Porto Alegre were tested.

Methods

We examined 325 blood samples from blood donors collected from October 2017 to July 2018. Blood was collected on filter paper and the DNA was extracted for single nucleotide polymorphisms (SNPs) analysis using the qualitative real time polymerase chain reaction.

Results

The calculated frequencies of each genetic variant in heterozygosity were 4% for the FV gene (g.1691G > A), 4% for the F2 gene (g.20210G > A) and 42% and 39% for methylenetetrahydrofolate reductase (MTHFR), g.677C > T and g.1298A > C, respectively. Only the genetic variants of MTHFR were found in homozygosity, with frequencies of 14% and 6% (g.677C > T and g.1298A > C), respectively.

Discussion

Altogether, these results describe the frequencies of genetic variants associated with venous thrombosis and hyperhomocysteinemia in the analyzed group and are important to enhance our current knowledge about the genetic profiles of Brazilian blood donors.

Determining the association of thrombophilic gene polymorphisms with recurrent pregnancy loss in Iranian women

OBJECTIVE

Thrombophilia is known to be associated with poor pregnancy outcomes. In this study, three thrombophilic gene polymorphisms, including EPCR (Ser219Gly), F11 (rs4253417) and F7 (323 Ins10) were investigated in an Iranian population of women in order to determine the correlation between thrombophilia and recurrent pregnancy loss (RPL).

METHODS

Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) were used to evaluate the frequency of three candidate thrombophilic risk factors for recurrent pregnancy loss. The frequencies of the polymorphisms were compared between the case (144 patients with a history of at least two miscarriages) and the control (150 healthy women with no abortion) group.

RESULTS

Our results show that EPCR and FVII polymorphisms of the patient and control group have the same genotype frequency, and the difference is not statistically significant (p-value > .05). Regarding FXI polymorphism, TT genotype frequency was higher in the patient group than the control group (p-value < .05); however, CT heterozygote form was higher in the control group compared to the patient group (p-value < .05).

CONCLUSION

In FXI polymorphism, T allele is possibly an RPL risk factor and C allele has a protective role. Thus, wild type FXI could be related to RPL, but EPCR and FVII polymorphism have no such correlation.

Hemostatic changes by thrombopoietin-receptor agonists in immune thrombocytopenia patients

Thrombopoietin receptor agonist (TPO-RA) treatment increases the thrombosis rate in immune thrombocytopenia (ITP). We hypothesize that TPO-RAs influence platelet function, global and secondary hemostasis and/or fibrinolysis. A systematic review was performed. If possible, data were compared between responders (relevant increase in platelet count), and non-responders. Twelve observational studies with 305 patients were included (responders (127/150 (85%))). There were indications that TPO-RA treatment enhanced platelet function, with respect to platelet-monocyte aggregates, soluble P-selectin, GPVI expression, and adhesion under flow. Studies addressing global and secondary hemostasis and fibrinolysis were scarce. Overall, no changes were found during TPO-RA treatment, apart from an accelerated clot formation and conflicting data on levels of plasminogen activator inhibitor (PAI)-1. The parameters that increased have previously been associated with thrombosis in other patient groups, and might contribute to the increased rate of thrombosis observed in TPO-RA-treated ITP patients.

ADAMTS13 activity, high VWF and FVIII levels in the pathogenesis of deep vein thrombosis

BACKGROUND

Deep vein thrombosis (DVT) is a common multi-factorial disease with a partially understood aetiology. Although the roles of high factor (F)VIII and von Willebrand factor (VWF) levels are recognized, that of ADAMTS13 is still unclear.

AIM

To assess the association between ADAMTS13 activity levels, VWF antigen (VWF:Ag) and FVIII coagulant activity (FVIII:C) levels and DVT.

MATERIALS AND METHODS

365 Italian DVT patients and 292 age- and sex-matched controls were considered. Plasma ADAMTS13 activity was measured using FRETS-VWF73 assay. VWF:Ag and FVIII:C were measured using immunoassay and one-stage clotting assay (ACL TOP analyzer), respectively. Quartile analyses were performed to evaluate the individual association between ADAMTS13 activity, VWF:Ag, FVIII:C and DVT. The combined effect of high VWF levels (> 4th quartile) and low ADAMTS13 levels (< 1st quartile) was evaluated using binary variables. All models were age- and sex-adjusted. Estimated risks were reported as Odds ratio (OR) with 95% confidence intervals (CI).

RESULTS

ADAMTS13 activity was lower in DVT patients (94% vs. 98% of controls). Patients with an ADAMTS13 activity <1st quartile (86%) showed a 1.6-fold increased risk of DVT (95%CI, 1.05-2.55). The combination of low ADAMTS13 activity and high VWF:Ag levels was associated with a 15-fold increased risk (95%CI, 7.80-33.80). VWF:Ag and FVIII:C were associated to DVT with a dose-response relationship.

CONCLUSIONS

ADAMTS13 activity < 86% was associated with a moderate risk of DVT. The co-presence of low ADAMTS13 activity and high VWF levels resulted in a strong synergistic effect on DVT risk. The association of VWF:Ag and FVIII:C with DVT was confirmed.

Lifestyle Moderates Genetic Risk of Venous Thromboembolism: The ARIC Study

OBJECTIVE

Venous thromboembolism (VTE) is a common disease that has a genetic basis. Lifestyle factors contribute to risk, but it is unknown whether healthy lifestyle can mitigate the genetic risk. We studied whether greater adherence to the American Heart Association's cardiovascular health metric, Life's Simple 7 (LS7), is associated with lower incidence of VTE in individuals across categories of a genetic risk score (GRS) for VTE. Approach AND RESULTS: We followed 9026 White participants from the ARIC (Atherosclerosis Risk in Communities) Study, a prospective cohort enrolled in 1987 to 1989 until 2015. We tested the joint associations with VTE of a validated VTE GRS comprising 5 well-known gene variants and baseline LS7 categories. There were 466 incident VTE events over 22.8 years. Participants with an optimal LS7 score had a lower incidence of VTE (3.9%) than those with inadequate LS7 (5.7%). Compared with the high GRS and inadequate LS7 group (hazard ratio=1), those with high GRS and optimal LS7 indeed had a reduced hazard ratio of VTE: 0.65 (95% CI, 0.48-0.89). The group with low GRS and optimal LS7 had the lowest hazard ratio of VTE (0.39 [95% CI, 0.25-0.61]). Of the LS7 components, in all GRS groups, the factor most strongly protective for VTE was normal weight.

CONCLUSIONS

Among people at low or high genetic risk for VTE, healthier lifestyle factors, particularly normal weight, were associated with a lower incidence of VTE. Further studies should determine the impact of lifestyle changes among patients at high genetic risk of VTE, such as in thrombophilic families.

Combined effects of five prothrombotic genotypes and cancer on the risk of a first venous thromboembolic event

BACKGROUND

The role of combined prothrombotic genotypes in cancer-related venous thromboembolism (VTE) is scarcely studied. We aimed to investigate the impact of a 5-single nucleotide polymorphism (SNP) score on the risk of VTE in patients with and without cancer using a population-based case-cohort.

METHODS

Cases with a first VTE (n = 1493) and a subcohort (n = 13 072) were derived from the Tromsø Study (1994-2012) and the Nord-Trøndelag Health Study (1995-2008). Five SNPs previously reported as a risk score were genotyped: ABO (rs8176719), F5 (rs6025), F2 (rs1799963), FGG (rs2066865), and F11 (rs2036914). Hazard ratios (HRs) for VTE were estimated according to cancer status and the number of risk alleles in the 5-SNP score (0-1, 2-3, and ≥4 alleles).

RESULTS

During a median follow-up of 12.3 years, 1496 individuals were diagnosed with cancer, of whom 232 experienced VTE. The VTE risk increased with the number of risk alleles in the 5-SNP score among subjects without and with cancer. In cancer-free subjects, the HR was 2.17 (95% confidence interval [CI] 1.79-2.62) for ≥4 versus 0-1 risk alleles. In cancer patients, the corresponding HR was 1.93 (95% CI 1.28-2.91). The combination of cancer and ≥4 risk alleles yielded a 17-fold (HR 17.1, 95% CI 12.5-23.4) higher risk of VTE compared with cancer-free subjects with 0-1 risk alleles.

CONCLUSION

The risk of VTE increases with the number of prothrombotic risk alleles in subjects with and without cancer, and the combination of prothrombotic risk alleles and cancer leads to a highly elevated risk of VTE.

The role of bone marrow-derived cells in venous thromboembolism

Venous thrombosis is a life-threatening condition with high morbidity and mortality. Abnormal functioning of different cells in the blood is an integral part of its pathogenesis. In this review, we describe the contribution of bone marrow-derived cells to the development of this debilitating disease. We present both epidemiological and clinical data demonstrating involvement of various cell types in venous thrombosis, and discuss potential mechanisms underlying these effects. Modern concepts including recently discovered new paradigms in thrombosis, such as neutrophil extracellular traps, mast cells, and polyphosphate, are summarized.

Profile of genetic variations in severely calcified carotid plaques by whole-exome sequencing

Background:

The precise mechanisms of carotid calcification and its clinical significance have not been established.

Methods:

We classified ten plaques from carotid endarterectomy patients into high- and low-calcified plaques based on the Agatston calcium scores. We performed whole-exome sequencing for genetic profiles with single nucleotide variations (SNVs), insertions, and deletions. Bioinformatic data mining was then conducted to disclose specific gene variations to either high- or low-calcified carotid plaques.

Results:

In the carotid plaques, G:C>A:T/C:G>T:A transitions as SNVs, insT after C/insC after A as insertions, and delA after G/delT after C as deletions were most frequently observed, but no significant difference was observed between the high- and low-calcified plaque groups in their proportion of base-pair substitution types. In the bioinformatic analysis, SNVs of ATP binding cassette subfamily C member 6 (ADCC6) were more commonly found in high-calcified plaques and SNVs of KLKB1 were more commonly found in low-calcified plaques compared to the other group. No new genetic variants related to calcification or atherosclerosis among those not registered in dbSNP was detected.

Conclusion:

Our findings clarified the features of base-pair substitutions in carotid plaques, showing no relation to calcification. However, genetic variants in ADCC6 relating to vascular calcification for high-calcified plaques, and in KLKB1 encoding kallikrein associated with vascular regulation of atherosclerosis for low-calcified plaques were more specifically extracted. These results contribute to a better understanding of the genetic basis of molecular activity and calcium formation in carotid plaques.

iTRAQ‑based proteomic analysis reveals potential regulatory networks in dust mite‑related asthma treated with subcutaneous allergen immunotherapy

Asthma is one of the most common childhood chronic diseases worldwide. Subcutaneous immunotherapy (SCIT) is commonly used in the treatment of house dust mite (HDM)‑related asthma in children. However, the therapeutic mechanism of SCIT in asthma remains unclear. The present study aimed to investigate the molecular biomarkers associated with HDM‑related asthma in asthmatic children prior and subsequent to SCIT treatment compared with those in healthy children via proteomic analysis. The study included a control group (30 healthy children), ‑Treatment group (30 children with HDM‑related allergic asthma) and +Treatment group (30 children with HDM‑related allergic asthma treated with SCIT). An isobaric labeling with relative and absolute quantification‑based method was used to analyze serum proteome changes to detect differentially expressed proteins, while functional enrichment and protein‑protein interaction network analysis were used to select candidate biomarkers. A total of 72 differentially expressed proteins were detected in the ‑Treatment, +Treatment and control groups. A total of 33 and 57 differentially expressed proteins were observed in the ‑Treatment vs. control and +Treatment vs. control groups, respectively. Through bioinformatics analysis, 5 candidate proteins [keratin 1 (KRT1), apolipoprotein B (APOB), fibronectin 1, antithrombin III (SERPINC1) and α‑1‑antitrypsin (SERPINA1)] were selected for validation by western blotting; among them, 4 proteins (KRT1, APOB, SERPINC1 and SERPINA1) showed robust reproducibility in asthma and control samples. This study illustrated the changes in proteome regulation following SCIT treatment for asthma. The 4 identified proteins may serve as potential biomarkers prior and subsequent to SCIT treatment, and help elucidate the molecular regulation mechanisms of SCIT to treat HDM‑related asthma.

Evaluation of relationship between KEAP1 gene and genetic susceptibility of deep vein thrombosis after orthopedic surgery in Han Chinese population

Deep vein thrombosis (DVT) is the blood clot formed in a vein deep in body, mostly occurred in the lower leg or thigh. Early studies indicate that DVT is a complex disorder affected by both environmental and genetic factors. Previous biological evidence have indicated that KEAP1 gene may play an important role in the pathogenesis of DVT. In the present study, we aimed to investigate the genetic association between genetic polymorphisms of KEAP1 gene and the risk of DVT in Han Chinese population. A total of 2558 study subjects comprised of 660 DVT following orthopedics surgery cases and 1898 controls were recruited as discovery sample. In addition, we have also recruited another independent sample sets including 704 DVT following orthopedics surgery cases and 1056 controls for replication. Ten tag SNPs located on KEAP1 gene were selected for genotyping. Single marker based association analyses were conducted at both allelic and genotypic levels. SNPs that passed the Bonferroni correction in the discovery stage were genotyped in the replication dataset. Bioinformatics tools including PolymiRTS, GTEx, STRING and Gene Ontology database were utilized to investigate the functional consequences of the significant SNPs. SNP rs3177696 was identified to be significantly associated with risk of DVT in the study subjects. The G allele of SNP rs3177696 was significantly related to decreased risk of DVT. Functional consequences of SNP rs3177696 were obtained based on bioinformatics analyses. The G allele of SNP rs3177696 was related to the increased gene expression level of KEAP1. In summary, we have identified KEAP1 gene to be a potential susceptible locus for DVT in Han Chinese population. Further bioinformatics analyses have provided supportive evidence for the functional consequence of the significant SNP.

Identification and functional characterization of CYP4V2 genetic variants exhibiting decreased activity of lauric acid metabolism

The objectives of the present study were to identify CYP4V2 genetic variants and characterize their functional consequences. A total of 26CYP4V2 genetic variants were identified, including seven novel variants in 60 randomly selected healthy subjects. Six protein-coding variants were studied, including three novel variants (L22V, R287T, and G410C) and three previously reported variants (R36S, Q259K, and H331P). The cDNA sequences encoding each amino acid variant and the wild-type CYP4V2 protein were cloned into the pcDNA/PDEST40 expression vector and transfected into eukaryotic 293T cells for overexpression of the CYP4V2 coding variants. CYP4V2 H331P and CYP4V2 G410C exhibited significant decreases in activity for lauric acid oxidation (20-30% of wild-type activity), when compared to the wildtype, which was correlated with low expression of CYP4V2 H331P and G410C substituted proteins. The other four CYP4V2 amino variants were comparable to wild-type CYP4V2 for lauric acid metabolism. The CYP4V2 H331P and G410C substitutions were predicted to cause a structural change through in silico analysis. In conclusion, the present study provides functional information about CYP4V2 genetic variants. These findings will be valuable for interpreting individual variations in phenotypes associated with CYP4V2 function in the clinical setting.

Dataset of GWAS-identified variants underlying venous thromboembolism susceptibility and linkage to cancer aggressiveness

Venous thromboembolism (VTE) is a common cardiovascular disease, for which several single nucleotide polymorphisms (SNPs) underlying susceptibility were identified. Apart from candidate gene approach, genome-wide association studies (GWAS) have contributed to the identification of novel VTE-associated SNPs, including some with no clear role in the haemostatic system. These genetic variants constitute potential cancer-related biomarkers, particularly predictive and prognostic biomarkers, as a two-way association between VTE and cancer is well established. The present dataset comprises the data obtained from GWAS performed to identify genetic variants associated with VTE risk. Furthermore, this dataset also comprises data regarding previously reported candidate gene and validation reports performed in adults of European ancestry that also analysed the VTE GWAS-identified variants. Lastly, to evaluate the impact of these genetic variants in carcinogenesis, a broad search was made, which has let us to establish putative links between several VTE-associated genes and cancer hallmarks in a review article entitled “Venous thromboembolism GWAS reported genetic makeup and the hallmarks of cancer: linkage to ovarian tumour behaviour”.

Black Patients Experience Highest Rates of Cancer-associated Venous Thromboembolism

PURPOSE

Cancer patients are at a higher risk of venous thromboembolism (VTE) than the general population. In the general population, blacks are at a higher risk of VTE compared with whites. The influence of race on cancer-associated VTE remains unexplored. We examined whether black cancer patients are at a higher risk of VTE and whether these differences are present in specific cancer types.

DESIGN

A retrospective study was performed in the largest safety net hospital of New England using a cohort of cancer patients characterized by a substantial number of nonwhites.

RESULTS

We identified 16,498 subjects with solid organ and hematologic malignancies from 2004 to 2018. Among them, we found 186 unique incident VTE events, of which the majority of the events accrued within the first 2 years of cancer diagnosis. Overall, blacks showed a 3-fold higher incidence of VTE (1.8%) compared with whites (0.6%; P<0.001). This difference was observed in certain cancer types such as lung, gastric and colorectal. In lung cancer, the odds of developing VTE in blacks was 2.77-times greater than those in white patients (confidence interval, 1.33-5.91; P=0.007). Despite the greater incidence of cancer-associated VTE in blacks, their Khorana risk score of VTE was not higher.

CONCLUSIONS

In a diverse cancer cohort, we observed a higher incidence of cancer-associated VTE in blacks compared with patients from other races. This study indicates the consideration of race in the risk assessment of cancer-associated VTE. It could also lead to future mechanistic studies aiming at identifying reasons for differential VTE risk depending on cancer type.

Burden of rare exome sequence variants in PROC gene is associated with venous thromboembolism: a population-based study

BACKGROUND

Rare coding mutations underlying deficiencies of antithrombin and proteins C and S contribute to familial venous thromboembolism (VTE). It is uncertain whether rare variants play a role in the etiology of VTE in the general population.

OBJECTIVES

We conducted a deep whole-exome sequencing (WES) study to investigate the associations between rare coding variants and the risk of VTE in two population-based prospective cohorts.

PATIENTS/METHODS

Whole-exome sequencing was performed in the Longitudinal Investigation of Thromboembolism Etiology (LITE), which combines the Atherosclerosis Risk in Communities (ARIC) study (316 incident VTE events among 3159 African Americans [AAs] and 458 incident VTEs among 7772 European Americans [EAs]) and the Cardiovascular Healthy Study (CHS; 60 incident VTEs among 1751 EAs). We performed gene-based tests of rare variants (allele frequency < 1%, exome-wide significance P < 1.47 × 10-6 ) separately in each study and ancestry group, and meta-analyzed the results for the EAs in ARIC and CHS.

RESULTS

In the meta-analysis of EAs, we identified one gene, PROC, in which the burden of rare, coding variants was significantly associated with increased risk of VTE (HR = 5.42 [3.11, 9.42] for carriers versus non-carriers, P = 2.27 × 10-9 ). In ARIC EAs, carriers of the PROC rare variants had on average 0.75 standard deviation (SD) lower concentrations of plasma protein C and 0.28 SD higher D-dimer (P < .05) than non-carriers. Adjustment for low protein C status did not eliminate the association of PROC burden with VTE. In AAs, rare coding PROC variants were not associated with VTE.

CONCLUSIONS

Rare coding variants in PROC contribute to increased VTE risk in EAs in this general population sample.

Genomic and transcriptomic association studies identify 16 novel susceptibility loci for venous thromboembolism

Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality. To advance our understanding of the biology contributing to VTE, we conducted a genome-wide association study (GWAS) of VTE and a transcriptome-wide association study (TWAS) based on imputed gene expression from whole blood and liver. We meta-analyzed GWAS data from 18 studies for 30 234 VTE cases and 172 122 controls and assessed the association between 12 923 718 genetic variants and VTE. We generated variant prediction scores of gene expression from whole blood and liver tissue and assessed them for association with VTE. Mendelian randomization analyses were conducted for traits genetically associated with novel VTE loci. We identified 34 independent genetic signals for VTE risk from GWAS meta-analysis, of which 14 are newly reported associations. This included 11 newly associated genetic loci (C1orf198, PLEK, OSMR-AS1, NUGGC/SCARA5, GRK5, MPHOSPH9, ARID4A, PLCG2, SMG6, EIF5A, and STX10) of which 6 replicated, and 3 new independent signals in 3 known genes. Further, TWAS identified 5 additional genetic loci with imputed gene expression levels differing between cases and controls in whole blood (SH2B3, SPSB1, RP11-747H7.3, RP4-737E23.2) and in liver (ERAP1). At some GWAS loci, we found suggestive evidence that the VTE association signal for novel and previously known regions colocalized with expression quantitative trait locus signals. Mendelian randomization analyses suggested that blood traits may contribute to the underlying risk of VTE. To conclude, we identified 16 novel susceptibility loci for VTE; for some loci, the association signals are likely mediated through gene expression of nearby genes.

Association of SERPINC1 Gene Polymorphism (rs2227589) With Pulmonary Embolism Risk in a Chinese Population

Background and Aims: Genetic variants in the gene SERPINC1 have been shown to be associated with antithrombin deficiency, which subsequently contributes to the susceptibility to venous thrombosis. However, several other studies have shown conflicting results regarding the association of SERPINC1 gene polymorphisms (rs2227589) with the risk of thrombosis. Hence, in the present study, we conducted a case-control study to further evaluate the association between the variant rs2227589 with antithrombin deficiency in pulmonary embolism (PTE). A pooled systematic analysis was also conducted to evaluate the risk of rs2227589 in venous thromboembolism (VTE) among multiple populations. Methods: This case-control study involved 101 patients and 199 healthy controls. The allele frequency of SERPINC1 variant rs2227589 was analyzed by Sequenom assay. Antithrombin anticoagulant activity was detected using an automatic coagulation analyzer. In addition, a pooled systematic analysis on 10 cohorts consisting of 5,518 patients with VTE and 8,935 controls was performed. Results: In total, 27 (26.7%) PTE subjects were diagnosed as having antithrombin deficiency. Our results showed that antithrombin plasma activity was slightly lower in T allele carriers than that in C allele carriers. However, there was no significant correlation between rs2227589 genotype and antithrombin anticoagulant activity. The recessive model showed that rs2227589 was significantly associated (p = 0.026) with an increased risk {odds ratio [OR]: 2.31, 95% confidence interval [CI] (1.09-4.89)} of Chinese PTE. The pooled systematic analysis of all case-control study and meta-analysis showed that rs2227589 polymorphism was associated with an increased risk of VTE in the additive model [OR: 1.09, 95% CI (1.01-1.18), P = 0.029] and dominant model [OR: 1.10, 95% CI (1.01-1.20), P = 0.034]. Conclusions: Our study demonstrated that variant rs2227589 is associated with an increased risk of PTE in a Chinese population but no correlation with antithrombin anticoagulant activity. However, pooled systematic analysis of multiple populations showed a significant association between rs2227589 and the risk of VTE in the additive and dominant genetic model.

Hemostasis-related gene polymorphisms and their epistatic relationship in women with idiopathic infertility

: A numerous factor can cause infertility, but around one of four reproductive failure cases remain unexplained and diagnosed as idiopathic infertility. In the past few decades, analysis of gene polymorphisms takes a significant place in pathogenesis of infertility. The aim of this study was to evaluate the possible role of hemostasis-related gene polymorphisms in unexplained infertility. The study includes 117 female patients with idiopathic infertility and 130 fertile women with at least one born child. Eight polymorphisms important for hemostasis (ITGB3 1565T>C, FV 1691G>A, FII 20210G>A, MTHFR 677C>T and 1298A>C, ATIII 786G>A, PAI-14G/5G and ACE I/D) were genotyped by real-time PCR system. The frequencies of alleles and genotypes of examined polymorphisms were analyzed in SPSS statistical program, whereas gene interactions were identified using the GMDR software. Examination of etiological factors has shown that family history is a significant factor in assessing individual risk for infertility. The alleles and genotypes frequency of FV 1691G>A and FII 20210G>A polymorphisms were statistically different between control and patient group leading to a greater risk for infertility. The analysis of epistatic relationship between examined hemostasis-related gene polymorphisms identified more complex high-risk genotypes associated with infertility. Our results suggest that positive family history could be important predictive factor for fertility problems, pointing to the potential hereditary basis of this condition. Polymorphisms FVL and FII prothrombin are independent risk factors for idiopathic infertility, whereas multilocus interactions approach should be taken into consideration for the future research.

Genetic profiling revealed an increased risk of venous thrombosis in the Hungarian Roma population

BACKGROUND

Besides modifiable risk factors, genetic susceptibility may also explain the high cardiovascular disease burden of the Roma population.

OBJECTIVES

Aim of this study was to define the genetic susceptibility of Hungarian Roma to venous thrombosis (VT) and comparing it to that of the general population.

METHODS

Fifty-two SNPs associated with VT (in F2, F5, F9, F11, F15, FGA, FGB, FGG, CYP4V2, KLKB1 and vWF) were selected and analyzed in the group of Roma (N = 962) and general (N = 1492) subjects collected by cross-sectional studies. Allele frequencies and genetic risk scores (GRS, unweighted and weighted) were computed for the study groups and compared to estimate the joint effects of SNPs.

RESULTS

The majority of the susceptible alleles were more prevalent in the Roma population, and both GRS and wGRS were found to be significantly higher in Roma than in the general population (GRS: 41.83 ± 5.78 vs. 41.04 ± 6.04; wGRS: 7.78 ± 1.28 vs. 7.46 ± 1.33, p = .001). Only 2.39% of subjects in the Roma population were in the bottom fifth of the wGRS (wGRS≤0.19) compared with 3.62% of those in the general population (p = .080); 2.88% of the general subjects were in the top fifth of the wGRS (wGRS≥10.02), while 4.26% of the Roma population were (p = .066).

CONCLUSION

In conclusion, the Roma population seems to have increased genetic susceptibility to VT. This might have important implications in the future in identifying possible new opportunities for targeted prevention and treatment for those subgroups in the populations who are at greater risk for VT development.

Genetic determinants of activity and antigen levels of contact system factors

Essentials Genetic variation may provide valuable insight into the role of the contact system in thrombosis. Explored associations of genetic variants with activity, antigen, and disease in RATIO study. Two novel loci were identified: KLKB1 rs4253243 for prekallikrein; KNG1 rs5029980 for HMWK levels. Contact system variants and haplotypes were not associated with myocardial infarction or stroke. SUMMARY: Background The complex, interdependent contact activation system has been implicated in thrombotic disease, although few genetic determinants of levels of proteins from this system are known. Objectives Our primary aim was to study the influence of common F11, F12, KLKB1, and KNG1 variants on factor (F) XI activity and FXI, FXII, prekallikrein (PK) and high-molecular-weight kininogen (HMWK) antigen levels, as well as the risk of myocardial infarction and ischemic stroke. Patients/methods We analyzed samples from all 630 healthy participants, 182 ischemic stroke patients and 216 myocardial infarction patients in the RATIO case-control study of women aged < 50 years. Forty-three tagging single nucleotide variants (SNVs) were genotyped to represent common genetic variation in the contact system genes. Antigen and activity levels were measured with sandwich-ELISA-based and one-stage clotting assays. We performed single variant, age-adjusted, linear regression analyses per trait and disease phenotype, assuming additive inheritance and determined conditionally independent associations. Haplotypes based on the lead SNV and all conditionally independent SNVs were tested for association with traits and disease. Results We identified two novel associations of KLKB1 SNV rs4253243 with PK antigen (βconditional = -12.38; 95% CI, -20.07 to -4.69) and KNG1 SNV rs5029980 with HMWK antigen (βconditional = 5.86; 95% CI, 2.40-9.32) and replicated previously reported associations in a single study. Further analyses probed whether the observed associations were indicative of linkage, pleiotropic effects or mediation. No individual SNVs or haplotypes were associated with the disease outcomes. Conclusion This study adds to current knowledge of how genetic variation influences contact system protein levels and clarifies interdependencies.