scholarly journals Common genetic variation indicates separate etiologies for periventricular and deep white matter hyperintensities

2019 ◽  
Author(s):  
Nicola J Armstrong ◽  
Karen A Mather ◽  
Muralidharan Sargurupremraj ◽  
Maria J Knol ◽  
Rainer Malik ◽  
...  

AbstractWe conducted a genome-wide association meta-analysis of two ischemic white matter disease subtypes in the brain, periventricular and deep white matter hyperintensities (PVWMH and DWMH). In 26,654 participants, we found 10 independent genome-wide significant loci only associated with PVWMH, four of which have not been described previously for total WMH burden (16q24.2, 17q21.31, 10q23.1, 7q36.1). Additionally, in both PVWMH and DWMH we observed the previous association of the 17q25.1 locus with total WMH. We found that both phenotypes have shared but also distinct genetic architectures, consistent with both different underlying and related pathophysiology. PVWMH had more extensive genetic overlap with small vessel ischemic stroke, and unique associations with several loci implicated in ischemic stroke. DWMH were characterized by associations with loci previously implicated in vascular as well as astrocytic and neuronal function. Our study confirms the utility of these phenotypes and identifies new candidate genes associated only with PVWMH.

Stroke ◽  
2020 ◽  
Vol 51 (7) ◽  
pp. 2111-2121 ◽  
Author(s):  
Nicola J. Armstrong ◽  
Karen A. Mather ◽  
Muralidharan Sargurupremraj ◽  
Maria J. Knol ◽  
Rainer Malik ◽  
...  

Background and Purpose: Periventricular white matter hyperintensities (WMH; PVWMH) and deep WMH (DWMH) are regional classifications of WMH and reflect proposed differences in cause. In the first study, to date, we undertook genome-wide association analyses of DWMH and PVWMH to show that these phenotypes have different genetic underpinnings. Methods: Participants were aged 45 years and older, free of stroke and dementia. We conducted genome-wide association analyses of PVWMH and DWMH in 26,654 participants from CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology), ENIGMA (Enhancing Neuro-Imaging Genetics Through Meta-Analysis), and the UKB (UK Biobank). Regional correlations were investigated using the genome-wide association analyses -pairwise method. Cross-trait genetic correlations between PVWMH, DWMH, stroke, and dementia were estimated using LDSC. Results: In the discovery and replication analysis, for PVWMH only, we found associations on chromosomes 2 ( NBEAL ), 10q23.1 ( TSPAN14/FAM231A ), and 10q24.33 ( SH3PXD2A). In the much larger combined meta-analysis of all cohorts, we identified ten significant regions for PVWMH: chromosomes 2 (3 regions), 6, 7, 10 (2 regions), 13, 16, and 17q23.1. New loci of interest include 7q36.1 ( NOS3 ) and 16q24.2. In both the discovery/replication and combined analysis, we found genome-wide significant associations for the 17q25.1 locus for both DWMH and PVWMH. Using gene-based association analysis, 19 genes across all regions were identified for PVWMH only, including the new genes: CALCRL (2q32.1), KLHL24 (3q27.1), VCAN (5q27.1), and POLR2F (22q13.1). Thirteen genes in the 17q25.1 locus were significant for both phenotypes. More extensive genetic correlations were observed for PVWMH with small vessel ischemic stroke. There were no associations with dementia for either phenotype. Conclusions: Our study confirms these phenotypes have distinct and also shared genetic architectures. Genetic analyses indicated PVWMH was more associated with ischemic stroke whilst DWMH loci were implicated in vascular, astrocyte, and neuronal function. Our study confirms these phenotypes are distinct neuroimaging classifications and identifies new candidate genes associated with PVWMH only.


Neurology ◽  
2019 ◽  
Vol 92 (8) ◽  
pp. e749-e757 ◽  
Author(s):  
Matthew Traylor ◽  
Daniel J. Tozer ◽  
Iain D. Croall ◽  
Danuta M. Lisiecka Ford ◽  
Abiodun Olubunmi Olorunda ◽  
...  

ObjectiveTo identify novel genetic associations with white matter hyperintensities (WMH).MethodsWe performed a genome-wide association meta-analysis of WMH volumes in 11,226 individuals, including 8,429 population-based individuals from UK Biobank and 2,797 stroke patients. Replication of novel loci was performed in an independent dataset of 1,202 individuals. In all studies, WMH were quantified using validated automated or semi-automated methods. Imputation was to either the Haplotype Reference Consortium or 1,000 Genomes Phase 3 panels.ResultsWe identified a locus at genome-wide significance in an intron of PLEKHG1 (rs275350, β [SE] = 0.071 [0.013]; p = 1.6 × 10−8), a Rho guanine nucleotide exchange factor that is involved in reorientation of cells in the vascular endothelium. This association was validated in an independent sample (overall p value, 2.4 × 10−9). The same single nucleotide polymorphism was associated with all ischemic stroke (odds ratio [OR] [95% confidence interval (CI)] 1.07 [1.03–1.12], p = 0.00051), most strongly with the small vessel subtype (OR [95% CI] 1.09 [1.00–1.19], p = 0.044). Previous associations at 17q25 and 2p16 reached genome-wide significance in this analysis (rs3744020; β [SE] = 0.106 [0.016]; p = 1.2 × 10−11 and rs7596872; β [SE] = 0.143 [0.021]; p = 3.4 × 10−12). All identified associations with WMH to date explained 1.16% of the trait variance in UK Biobank, equivalent to 6.4% of the narrow-sense heritability.ConclusionsGenetic variation in PLEKHG1 is associated with WMH and ischemic stroke, most strongly with the small vessel subtype, suggesting it acts by promoting small vessel arteriopathy.


2017 ◽  
Vol 3 (5) ◽  
pp. e185 ◽  
Author(s):  
Ashley Beecham ◽  
Chuanhui Dong ◽  
Clinton B. Wright ◽  
Nicole Dueker ◽  
Adam M. Brickman ◽  
...  

Objective:To investigate genetic variants influencing white matter hyperintensities (WMHs) in the understudied Hispanic population.Methods:Using 6.8 million single nucleotide polymorphisms (SNPs), we conducted a genome-wide association study (GWAS) to identify SNPs associated with WMH volume (WMHV) in 922 Hispanics who underwent brain MRI as a cross-section of 2 community-based cohorts in the Northern Manhattan Study and the Washington Heights–Inwood Columbia Aging Project. Multiple linear modeling with PLINK was performed to examine the additive genetic effects on ln(WMHV) after controlling for age, sex, total intracranial volume, and principal components of ancestry. Gene-based tests of association were performed using VEGAS. Replication was performed in independent samples of Europeans, African Americans, and Asians.Results:From the SNP analysis, a total of 17 independent SNPs in 7 genes had suggestive evidence of association with WMHV in Hispanics (p < 1 × 10−5) and 5 genes from the gene-based analysis with p < 1 × 10−3. One SNP (rs9957475 in GATA6) and 1 gene (UBE2C) demonstrated evidence of association (p < 0.05) in the African American sample. Four SNPs with p < 1 × 10−5 were shown to affect binding of SPI1 using RegulomeDB.Conclusions:This GWAS of 2 community-based Hispanic cohorts revealed several novel WMH-associated genetic variants. Further replication is needed in independent Hispanic samples to validate these suggestive associations, and fine mapping is needed to pinpoint causal variants.


Neurology ◽  
2015 ◽  
Vol 86 (2) ◽  
pp. 146-153 ◽  
Author(s):  
Matthew Traylor ◽  
Cathy R. Zhang ◽  
Poneh Adib-Samii ◽  
William J. Devan ◽  
Owen E. Parsons ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
pp. 16 ◽  
Author(s):  
Imama Naqvi ◽  
Emi Hitomi ◽  
Richard Leigh

Objective: To report a patient in whom an acute ischemic stroke precipitated chronic blood-brain barrier (BBB) disruption and expansion of vascular white matter hyperintensities (WMH) into regions of normal appearing white matter (NAWM) during the following year. Background: WMH are a common finding in patients with vascular risk factors such as a history of stroke. The pathophysiology of WMH is not fully understood; however, there is growing evidence to suggest that the development of WMH may be preceded by the BBB disruption in the NAWM. Methods: We studied a patient enrolled in the National Institutes of Health Natural History of Stroke Study who was scanned with magnetic resonance imaging (MRI) after presenting to the emergency room with an acute stroke. After a treatment with IV tPA, she underwent further MRI scanning at 2 h, 24 h, 5 days, 30 days, 90 days, 6 months, and 1-year post stroke. BBB permeability images were generated from the perfusion weighted imaging (PWI) source images. MRIs from each time point were co-registered to track changes in BBB disruption and WMH over time. Results: An 84-year-old woman presented after acute onset right hemiparesis, right-sided numbness and aphasia with an initial NIHSS of 13. MRI showed diffusion restriction in the left frontal lobe and decreased blood flow on perfusion imaging. Fluid attenuated inversion recovery (FLAIR) imaging showed bilateral confluent WMH involving the deep white matter and periventricular regions. She was treated with IV tPA without complication and her NIHSS improved initially to 3 and ultimately to 0. Permeability maps identified multiple regions of chronic BBB disruption remote from the acute stroke, predominantly spanning the junction of WMH and NAWM. The severity of BBB disruption was greatest at 24 h after the stroke but persisted on subsequent MRI scans. Progression of WMH into NAWM over the year of observation was detected bilaterally but was most dramatic in the regions adjacent to the initial stroke. Conclusions: WMH-associated BBB disruption may be exacerbated by an acute stroke, even in the contralateral hemisphere, and can persist for months after the initial event. Transformation of NAWM to WMH may be evident in areas of BBB disruption within a year after the stroke. Further studies are needed to investigate the relationship between chronic BBB disruption and progressive WMH in patients with a history of cerebrovascular disease and the potential for acute stroke to trigger or exacerbate the process leading to the development of WMH.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Sara Coles ◽  
Stephanie Giamberardino ◽  
Carol Haynes ◽  
Ruicong She ◽  
Hongsheng Gui ◽  
...  

Background: Exercise has shown benefit in patients with systolic heart failure, including in the clinical trial Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training (HF-ACTION). There is heterogeneity in who derives benefit from exercise, and the biologic mechanisms of favorable response to exercise in systolic heart failure are not well understood. Hypothesis: Genetic variation is an underlying factor influencing heterogeneity in response to exercise in patients with systolic heart failure. Methods: The HF-ACTION trial randomized individuals with systolic heart failure (left ventricular ejection fraction <35%) to supervised exercise versus usual care. In this study, we performed a genome wide association study (GWAS) in the HF-ACTION biorepository using the Axiom Biobank1 genotyping array (13,403,591 single nucleotide polymorphisms [SNPs] after quality control on directly genotyped and 1000 genomes imputed data), in N=377 study subjects who completed the supervised exercise arm. Using change in peak VO2 as our outcome, we ran within-ancestry GWASes, modeling SNP effects as both additive and dominant, and conducted across-ancestry meta-analysis within each genetic model. Results: Five loci met genome-wide significance in the European ancestry analyses, 5 loci in the African ancestry, and 8 in the meta-analyses. The two most significantly associated loci across both additive and dominant meta-analysis models were rs111577308 located in the histone acetylation for transcription elongator complex 3 gene ( ELP3, p=1.212x10 -9 ) and rs75444785 located in the phosphodiesterase 4D gene ( PDE4D , p=1.565x10 -9 ). ELP3 is responsible for histone modifications related to DNA transcription factor complexes, and PDE4D is involved in cyclic AMP cell signaling. In silico analysis of these loci showed that they are in linkage with regions associated with skeletal muscle and peripheral vascular disease phenotypes. Conclusions: Using a genome-wide association study in a well-phenotyped clinical trial of exercise in systolic heart failure, we found common genetic variants in genes involved in DNA transcription histone modification and cyclic AMP cell signaling that are associated with a more favorable response to exercise.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Stacy C Brown ◽  
Cameron Both ◽  
Julian N Acosta ◽  
Natalia Szejko ◽  
Victor Torres ◽  
...  

Background: Several genetic susceptibility risk loci for ischemic stroke have been identified. However, the relative dearth of genetic data from populations of non-European ancestry has the potential to create disparities in access to genomics-based precision medicine strategies. Individuals of Native Hawaiian ancestry represent a particularly understudied group in stroke genomics research despite facing high rates of cerebrovascular disease. Hypothesis: Genetic variants associated with stroke differ between Native Hawaiians and previously studied groups of predominantly European ancestry. Methods: We conducted a genome-wide (GW) association study of stroke and myocardial infarction (MI) in an adult population of Native Hawaiian ancestry, using data from the Multiethnic Cohort study (MEC). Genetic information was ascertained via genome-wide array genotyping using the AB OpenArray and TaqMan platforms followed by imputation to 1000 Genomes reference panels. We pursued replication of variants that were GW significant (p<5x10 -8 ) or yielded suggestive associations (p<5x10 -7 ) in the prior stroke GW association study MEGASTROKE. Results: We identified 2,104 individuals (1,089 [51.8%] female) of Native Hawaiian ancestry, including 173 cases and 1,931 controls. We identified one novel susceptibility risk locus at a narrow intronic region located at chromosome q26.2 (top associated SNP 3:169096251, OR 2.48, 95%CI 1.81-3.41; p=1.93x10 -8 ), overlying the MECOM gene. We also identified 9 other suggestive risk loci at p<5x10 -7 . When replicating in MEGASTROKE, q26.2 did not have available counterpart variants to analyze, and 3 out of 9 suggestive signals were associated with ischemic stroke subtypes at p<0.05. Conclusions: We report the first GW association study of ischemic stroke and myocardial infarction in a Native Hawaiian population. We identified one susceptibility risk locus at q26.2, located in a narrow intronic region of MECOM, a gene that codes for a histone-lysine N-methyltransferase that has transcriptional regulation and oncoprotein functions. The lack of available replication data for this locus in the large MEGASTROKE collaboration emphasizes the importance of developing genomic resources across ancestral groups.


Sign in / Sign up

Export Citation Format

Share Document