Single nucleotide variations in ZBTB46 are associated with post-thrombolytic parenchymal haematoma

A multitrait genetic study of hemostatic factors and hemorrhagic transformation after stroke treatment

BACKGROUND

Thrombolytic recombinant tissue plasminogen activator (r-tPA) treatment is the only pharmacologic intervention available in the ischemic stroke acute phase. This treatment is associated with an increased risk of intracerebral hemorrhages, known as hemorrhagic transformations (HTs), which worsen the patient's prognosis.

OBJECTIVES

To investigate the association between genetically determined natural hemostatic factors' levels and increased risk of HT after r-tPA treatment.

METHODS

Using data from genome-wide association studies on the risk of HT after r-tPA treatment and data on 7 hemostatic factors (factor [F]VII, FVIII, von Willebrand factor [VWF], FXI, fibrinogen, plasminogen activator inhibitor-1, and tissue plasminogen activator), we performed local and global genetic correlation estimation multitrait analyses and colocalization and 2-sample Mendelian randomization analyses between hemostatic factors and HT.

RESULTS

Local correlations identified a genomic region on chromosome 16 with shared covariance: fibrinogen-HT, P = 2.45 × 10-11. Multitrait analysis between fibrinogen-HT revealed 3 loci that simultaneously regulate circulating levels of fibrinogen and risk of HT: rs56026866 (PLXND1), P = 8.80 × 10-10; rs1421067 (CHD9), P = 1.81 × 10-14; and rs34780449, near ROBO1 gene, P = 1.64 × 10-8. Multitrait analysis between VWF-HT showed a novel common association regulating VWF and risk of HT after r-tPA at rs10942300 (ZNF366), P = 1.81 × 10-14. Mendelian randomization analysis did not find significant causal associations, although a nominal association was observed for FXI-HT (inverse-variance weighted estimate [SE], 0.07 [-0.29 to 0.00]; odds ratio, 0.87; 95% CI, 0.75-1.00; raw P = .05).

CONCLUSION

We identified 4 shared loci between hemostatic factors and HT after r-tPA treatment, suggesting common regulatory mechanisms between fibrinogen and VWF levels and HT. Further research to determine a possible mediating effect of fibrinogen on HT risk is needed.

Association of IL-6 rs1800795, but not TNF-α rs1800629, and IL-1β rs16944 polymorphisms' genotypes with recovery of ischemic stroke patients following thrombolysis

OBJECTIVES

Inflammatory cytokines like tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 can cause brain injury, slow recovery, and adverse effects (ADEs) in ischemic stroke (IS) patients treated with recombinant tissue plasminogen activator (rtPA). We explored the relationship between selected polymorphisms within TNF-α, IL-1β and IL-6 genes, and post-IS outcome and ADEs in patients treated with rtPA.

METHODS

One hundred and sixty-six patients with IS treated with rtPA were included in this study. The modified Rankin Scale (mRS) was used to assess functional recovery 3 months after IS likewise thrombolytic therapy efficacy. Patients were classified into groups with favorable (0-1) or poor recovery based on their mRS score at the ninetieth day post-IS. During hospitalization, ADEs following rtPA were monitored. TNF-α-308 G/A (rs1800629), IL-1β-511 G/A (rs16944), and IL-6-174 G/C (rs1800795) polymorphisms were genotyped using Real-Time PCR. SPSS software version 22.0 was used for statistical analyses.

RESULTS

Patients with the TNF-α-308 G/A GG genotype had a higher mean NIHSS value at admission (12.75 ± 5.176) than those carrying A-allele (10.56 ± 3.979;p = 0.016). Individuals with the CC genotype of the IL-6-174 G/C polymorphism had significantly lower NIHSS scores (8.79 ± 5.053) than those with G-allele (12.06 ± 6.562) 24 hours after rtPA (p = 0.050). Patients with the GG genotype of the IL-6-174 G/C polymorphism had a significantly poorer outcome (p = 0.024; OR = 2.339; 95%CI 1.121-4.880), while patients who were G-allele carriers of the Il-6-174 G/C polymorphism and had the AA genotype of the IL-1β-511 G/A polymorphism were statistically significantly more likely to experience hemorrhagic transformation (p = 0.046; OR = 2.7273; 95%CI 1.0414-7.1426).

CONCLUSION

GG genotype of the IL-6-174 G/C polymorphism is associated with poor recovery after IS treated with rtPA therapy.

A potential relationship between MMP-9 rs2250889 and ischemic stroke susceptibility

Purpose

Ischemic stroke (IS), a serious cerebrovascular disease, greatly affects people's health and life. Genetic factors are indispensable for the occurrence of IS. As a biomarker for IS, the MMP-9 gene is widely involved in the pathophysiological process of IS. This study attempts to find out the relationship between MMP-9 polymorphisms and IS susceptibility.

Methods

A total of 700 IS patients and 700 healthy controls were recruited. The single nucleotide polymorphism (SNP) markers of the MMP-9 gene were genotyped by the MassARRAY analyzer. Multifactor dimensionality reduction (MDR) was applied to generate SNP-SNP interaction. Furthermore, the relationship between genetic variations (allele and genotype) of the MMP-9 gene and IS susceptibility was analyzed by calculating odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Our results demonstrated that rs2250889 could significantly increase the susceptibility to IS in the codominant, dominant, overdominant, and log-additive models (p < 0.05). Further stratification analysis showed that compared with the control group, rs2250889 was associated with IS risk in different case groups (age, female, smoking, and non-drinking) (p < 0.05). Based on MDR analysis, rs2250889 was the best model for predicting IS risk (cross-validation consistency: 10/10, OR = 1.56 (1.26-1.94), p < 0.001).

Conclusion

Our study preliminarily confirmed that SNP rs2250889 was significantly associated with susceptibility to IS.

Genome-Wide Studies in Ischaemic Stroke: Are Genetics Only Useful for Finding Genes?

Ischaemic stroke is a complex disease with some degree of heritability. This means that heritability factors, such as genetics, could be risk factors for ischaemic stroke. The era of genome-wide studies has revealed some of these heritable risk factors, although the data generated by these studies may also be useful in other disciplines. Analysis of these data can be used to understand the biological mechanisms associated with stroke risk and stroke outcome, to determine the causality between stroke and other diseases without the need for expensive clinical trials, or to find potential drug targets with higher success rates than other strategies. In this review we will discuss several of the most relevant studies regarding the genetics of ischaemic stroke and the potential use of the data generated.

Pharmacogenetics studies in stroke patients treated with rtPA: a review of the most interesting findings

Recombinant tissue-plasminogen activator (rtPA) is the only drug used during the acute phase of stroke. Despite its important benefits, a percentage of patients suffer symptomatic hemorrhagic transformations or a lack of early recanalization rates. These undesirable effects are associated with acute neurological and long-term functional deterioration. For the past 20 years, pharmacogenetic studies have tried to find the genetic risk factors associated with rtPA response. Most of these studies have used a gene-candidate strategy; however, recent genome-wide association studies have emerged indicating that genetic predisposition could modulate rtPA response. This review summarizes the most interesting findings in this field, including which genes and genetic variations are associated with hemorrhagic transformations and recanalization rates after thrombolytic therapy.

Stroke Genetics: Turning Discoveries into Clinical Applications

The field of medical and population genetics in stroke is moving at a rapid pace and has led to unanticipated opportunities for discovery and clinical applications. Genome-wide association studies have highlighted the role of specific pathways relevant to etiologically defined subtypes of stroke and to stroke as a whole. They have further offered starting points for the exploration of novel pathways and pharmacological strategies in experimental systems. Mendelian randomization studies continue to provide insights in the causal relationships between exposures and outcomes and have become a useful tool for predicting the efficacy and side effects of drugs. Additional applications that have emerged from recent discoveries include risk prediction based on polygenic risk scores and pharmacogenomics. Among the topics currently moving into focus is the genetics of stroke outcome. While still at its infancy, this field is expected to boost the development of neuroprotective agents. We provide a brief overview on recent progress in these areas.

RP11-362K2.2:RP11-767I20.1 Genetic Variation Is Associated with Post-Reperfusion Therapy Parenchymal Hematoma. A GWAS Meta-Analysis

Stroke is one of the most common causes of death and disability. Reperfusion therapies are the only treatment available during the acute phase of stroke. Due to recent clinical trials, these therapies may increase their frequency of use by extending the time-window administration, which may lead to an increase in complications such as hemorrhagic transformation, with parenchymal hematoma (PH) being the more severe subtype, associated with higher mortality and disability rates. Our aim was to find genetic risk factors associated with PH, as that could provide molecular targets/pathways for their prevention/treatment and study its genetic correlations to find traits sharing genetic background. We performed a GWAS and meta-analysis, following standard quality controls and association analysis (fastGWAS), adjusting age, NIHSS, and principal components. FUMA was used to annotate, prioritize, visualize, and interpret the meta-analysis results. The total number of patients in the meta-analysis was 2034 (216 cases and 1818 controls). We found rs79770152 having a genome-wide significant association (beta 0.09, p-value 3.90 × 10⁻⁸) located in the RP11-362K2.2:RP11-767I20.1 gene and a suggestive variant (rs13297983: beta 0.07, p-value 6.10 × 10⁻⁸) located in PCSK5 associated with PH occurrence. The genetic correlation showed a shared genetic background of PH with Alzheimer’s disease and white matter hyperintensities. In addition, genes containing the ten most significant associations have been related to aggregated amyloid-β, tau protein, white matter microstructure, inflammation, and matrix metalloproteinases.