A study of alpha1 antichymotrypsin gene polymorphism in Indian stroke patients

Genetic risk of Spontaneous intracerebral hemorrhage: Systematic review and future directions

BACKGROUND

Although highly heritable, few genes have been linked to spontaneous intracerebral hemorrhage (SICH), which does not currently have any evidence-based disease-modifying therapy. Individuals of African ancestry are especially susceptible to SICH, even more so for indigenous Africans. We systematically reviewed the genetic variants associated with SICH and examined opportunities for rapidly advancing SICH genomic research for precision medicine.

METHOD

We searched the National Human Genome Research Institute-European Bioinformatics Institute (NHGRI-EBI) Genome Wide Association Study (GWAS) catalog and PubMed for original research articles on genetic variants associated with SICH as of 15 June 2019 using the PRISMA guideline.

RESULTS

Eight hundred and sixty-four articles were identified using pre-specified search criteria, of which 64 met the study inclusion criteria. Among eligible articles, only 9 utilized GWAS approach while the rest were candidate gene studies. Thirty-eight genetic loci were found to be variously associated with the risk of SICH, hematoma volume, functional outcome and mortality, out of which 8 were from GWAS including APOE, CR1, KCNK17, 1q22, CETP, STYK1, COL4A2 and 17p12. None of the studies included indigenous Africans.

CONCLUSION

Given this limited information on the genetic contributors to SICH, more genomic studies are needed to provide additional insights into the pathophysiology of SICH, and develop targeted preventive and therapeutic strategies. This call for additional investigation of the pathogenesis of SICH is likely to yield more discoveries in the unexplored indigenous African populations which also have a greater predilection.

High Mobility Group Protein B1 (HMGB1) and Interleukin-1β as Prognostic Biomarkers of Epilepsy in Children

The present study examined whether serum biomarkers can predict the prognosis of childhood epilepsy, including seizure frequency, electroencephalographic (EEG) changes, and cognitive impairment. We measured serum concentrations of high mobility group protein B1 (HMGB1), interleukin-1β (IL-1β), S100 calcium-binding protein B (S-100B), glial fibrillary acidic protein (GFAP), and α1-antichymotrypsin (AACT) in 180 children with new-onset epilepsy and 40 healthy children. Cognitive evaluations were performed 18 months after the initial seizure episodes at diagnosis (ie, baseline visit). The relationship between serum biomarkers and epilepsy prognosis was investigated using Pearson correlation coefficients, logistic regression analyses, and receiver operating characteristic curves. Sixty-seven patients had generalized tonic-clonic seizures, 92 had focal motor seizures, and 21 had epileptic spasms. Serum concentrations of HMGB1, IL-1β, S-100B, and GFAP were significantly higher in the epilepsy group within 24 hours of a seizure episode than in the control group. Furthermore, HMGB1 and IL-1β were significant predictors of epilepsy prognosis. Receiver operating characteristic curve analysis revealed that HMGB1 could more accurately predict seizure frequency than IL-1β; when the serum concentration of HMGB1 was >9.625 ng/mL, there was 80.6% sensitivity and 92.5% specificity for predicting seizure frequency reduction. In conclusion, HMGB1 and IL-1β have a predictive value for epilepsy prognosis in children.

Application of Single-Nucleotide Polymorphism-Related Risk Estimates in Identification of Increased Genetic Susceptibility to Cardiovascular Diseases: A Literature Review

Background

Although largely preventable, cardiovascular diseases (CVDs) are the biggest cause of death worldwide. Common complex cardiovascular disorders (e.g., coronary heart disease, hypertonia, or thrombophilia) result from a combination of genetic alterations and environmental factors. Recent advances in the genomics of CVDs have fostered huge expectations about future use of susceptibility variants for prevention, diagnosis, and treatment. Our aim was to summarize the latest developments in the field from a public health perspective focusing on the applicability of data on single-nucleotide polymorphisms (SNPs), through a systematic review of studies from the last decade on genetic risk estimating for common CVDs.

Methods

Several keywords were used for searching the PubMed, Embase, CINAHL, and Web of Science databases. Recent advances were summarized and structured according to the main public health domains (prevention, early detection, and treatment) using a framework suggested recently for translational research. This framework includes four recommended phases: “T1. From gene discovery to candidate health applications; T2. From health application to evidence-based practice guidelines; T3. From evidence-based practice guidelines to health practice; and T4. From practice to population health impacts.”

Results

The majority of translation research belongs to the T1 phase “translation of basic genetic/genomic research into health application”; there are only a few population-based impacts estimated. The studies suggest that an SNP is a poor estimator of individual risk, whereas an individual’s genetic profile combined with non-genetic risk factors may better predict CVD risk among certain patient subgroups. Further research is needed to validate whether these genomic profiles can prospectively identify individuals at risk to develop CVDs. Several research gaps were identified: little information is available on studies suggesting “Health application to evidence-based practice guidelines”; no study is available on “Guidelines to health practice.” It was not possible to identify studies that incorporate environmental or lifestyle factors in the risk estimation.

Conclusion

Currently, identifying populations having a larger risk of developing common CVDs may result in personalized prevention programs by reducing people’s risk of onset or disease progression. However, limited evidence is available on the application of genomic results in health and public health practice.

Is Alpha-1 Antichymotrypsin Gene Polymorphism a Risk Factor for Primary Intracerebral Hemorrhage? A Case-Control Study and Meta-Analysis

Background

Alpha-1 antichymotrypsin (ACT) signal peptide A/T polymorphism has been suggested to play a role in various brain diseases with arterial wall pathology. We conducted a case-control study and a meta-analysis to evaluate the association between this polymorphism and risk of primary intracerebral hemorrhage.

Material/Methods

A total of 188 patients and 200 age- and sex-matched healthy controls were enrolled in our case-control study. The ACT polymorphism was genotyped by PCR-LDR. Further meta-analysis was conducted by searching literature from PUBMED, EMBASE, and Chinese National Knowledge Infrastructure databases until December 2014, then combining data using STATA10.0.

Results

Similar genotype distribution was detected between PICH patients and healthy controls (p=0.523). Further analysis based on hypertension and location of hemorrhage did not observe significant association. Multiple logistic regression analysis also failed to identify ACT polymorphism as an independent risk factor for PICH. With regard to meta-analysis, a total of 6 case-control studies including 932 PICH patients and 1140 controls were enrolled. Pooled ORs failed to detect a significant association of ACT signal peptide A/T polymorphism with PICH (dominant model: OR=1.03, 95%CI=0.72–1.46; recessive model: OR=1.08, 95%CI=0.88–1.32). Subgroup analysis based on hypertension revealed no association in hypertensive PICH or in normotensive PICH.

Conclusions

Our case-control study in a Chinese population did not detect a significant association between ACT signal peptide A/T polymorphism and PICH. Moreover, meta-analysis combining data from relevant studies failed to provide evidence for the association. Further well-designed studies with larger sample sizes are warranted to verify our findings.

Detailed analysis of gene polymorphisms associated with ischemic stroke in South Asians

The burden of stroke is disproportionately high in the South Asian subcontinent with South Asian ethnicity conferring a greater risk of ischemic stroke than European ancestry regardless of country inhabited. While genes associated with stroke in European populations have been investigated, they remain largely unknown in South Asians. We conducted a comprehensive meta-analysis of known genetic polymorphisms associated with South Asian ischemic stroke, and compared effect size of the MTHFR C677T-stroke association with effect sizes predicted from homocysteine-stroke association. Electronic databases were searched up to August 2012 for published case control studies investigating genetic polymorphisms associated with ischemic stroke in South Asians. Pooled odds ratios (OR) for each gene-disease association were calculated using a random-effects model. We identified 26 studies (approximately 2529 stroke cases and 2881 controls) interrogating 33 independent genetic polymorphisms in 22 genes. Ten studies described MTHFR C677T (108 with TT genotype and 2018 with CC genotype) -homocysteine relationship and six studies (735 stroke cases and 713 controls) described homocysteine-ischemic stroke relationship. Risk association ORs were calculated for ACE I/D (OR 5.00; 95% CI, 1.17–21.37; p = 0.03), PDE4D SNP 83 (OR 2.20; 95% CI 1.21–3.99; p = 0.01), PDE4D SNP 32 (OR 1.57; 95% CI 1.01–2.45, p = 0.045) and IL10 G1082A (OR 1.44; 95% CI, 1.09–1.91, p = 0.01). Significant association was observed between elevated plasma homocysteine levels and MTHFR/677 TT genotypes in healthy South Asians (Mean difference (ΔX) 5.18 µmol/L; 95% CI 2.03–8.34: p = 0.001). Our results demonstrate that the genetic etiology of ischemic stroke in South Asians is broadly similar to the risk conferred in Europeans, although the dataset is considerably smaller and warrants the same clinical considerations for risk profiling.

Recurrent intracerebral hemorrhage in patients with hypertension is associated with APOE gene polymorphism: a preliminary study

BACKGROUND

Recurrent intracerebral hemorrhage (ICH) in patients with hypertension has been reported in Asia and is attributed to poor control of blood pressure, but there may be a genetic basis. This study evaluates the roles of apolipoprotein E (APOE) and α-1 antichymotrypsin (ACT) genes in patients with recurrent hypertensive ICH and compares patients with nonrecurring hypertensive ICH and normal controls.

METHODS

Thirty-three recurrent and 101 nonrecurrent patients with hypertension and ICH were included. The demographic, stroke risk factors, and computed tomographic or magnetic resonance imaging findings were recorded. Magnetic resonance angiography or digital subtraction angiography and vasculitic profile were done in recurrent group to exclude secondary causes of ICH. APOE and ACT gene polymorphisms were assessed with polymerase chain reaction studies in patients with ICH and 188 healthy controls.

RESULTS

The demographic and clinical variables were similar in patients with recurrent and nonrecurrent ICH, but patients with recurrent ICH were older (61.1 vs 57.2 years). In the recurrent ICH group, only 7 (10%) out of 69 episodes were lobar; the remaining were deep-seated hematomas. In the nonrecurrent group, 7 (6.9%) patients had lobar ICH. The E2 (odds ratio 4.32; 95% confidence interval 1.65-11.28; P = .003) and E4 alleles of APOE (odds ratio 11.33; 95% confidence interval 5.37-23.02; P < .0001) were significantly related to recurrent ICH compared to healthy controls. The E4 allele was also independently related to recurrent compared to nonrecurrent ICH, even after adjustment for stroke risk factors (odds ratio 25.99; 95% confidence interval 11.65-57.97; P < .0001). ACT gene polymorphism, however, was not related to recurrent ICH compared to controls and nonrecurrent ICH.

CONCLUSIONS

APOE polymorphism may contribute to the recurrence of hypertensive ICH.

Stroke in young in India

Stroke in young has special significance in developing countries. This is so because some etiologies like cardioembolic infections are more common than in developed countries, and the affection of economically productive group adds further to the overall disease burden. The paper discusses the burden of stroke in young and its implications in a developing country like India along with an approach to identifying different causes that are known to occur in this age group.