@article {1323, title = {Meta-analysis of genome-wide association studies from the CHARGE consortium identifies common variants associated with carotid intima media thickness and plaque.}, journal = {Nat Genet}, volume = {43}, year = {2011}, month = {2011 Sep 11}, pages = {940-7}, abstract = {

Carotid intima media thickness (cIMT) and plaque determined by ultrasonography are established measures of subclinical atherosclerosis that each predicts future cardiovascular disease events. We conducted a meta-analysis of genome-wide association data in 31,211 participants of European ancestry from nine large studies in the setting of the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. We then sought additional evidence to support our findings among 11,273 individuals using data from seven additional studies. In the combined meta-analysis, we identified three genomic regions associated with common carotid intima media thickness and two different regions associated with the presence of carotid plaque (P < 5 {\texttimes} 10(-8)). The associated SNPs mapped in or near genes related to cellular signaling, lipid metabolism and blood pressure homeostasis, and two of the regions were associated with coronary artery disease (P < 0.006) in the Coronary Artery Disease Genome-Wide Replication and Meta-Analysis (CARDIoGRAM) consortium. Our findings may provide new insight into pathways leading to subclinical atherosclerosis and subsequent cardiovascular events.

}, keywords = {Adult, Aged, Aging, Atherosclerosis, Carotid Intima-Media Thickness, Cohort Studies, Coronary Artery Disease, European Continental Ancestry Group, Genetic Loci, Genetic Predisposition to Disease, Genome, Human, Genome-Wide Association Study, Genotype, Heart, Humans, Middle Aged, Phenotype, Plaque, Atherosclerotic, Polymorphism, Single Nucleotide, Risk Factors}, issn = {1546-1718}, doi = {10.1038/ng.920}, author = {Bis, Joshua C and Kavousi, Maryam and Franceschini, Nora and Isaacs, Aaron and Abecasis, Goncalo R and Schminke, Ulf and Post, Wendy S and Smith, Albert V and Cupples, L Adrienne and Markus, Hugh S and Schmidt, Reinhold and Huffman, Jennifer E and Lehtim{\"a}ki, Terho and Baumert, Jens and M{\"u}nzel, Thomas and Heckbert, Susan R and Dehghan, Abbas and North, Kari and Oostra, Ben and Bevan, Steve and Stoegerer, Eva-Maria and Hayward, Caroline and Raitakari, Olli and Meisinger, Christa and Schillert, Arne and Sanna, Serena and V{\"o}lzke, Henry and Cheng, Yu-Ching and Thorsson, Bolli and Fox, Caroline S and Rice, Kenneth and Rivadeneira, Fernando and Nambi, Vijay and Halperin, Eran and Petrovic, Katja E and Peltonen, Leena and Wichmann, H Erich and Schnabel, Renate B and D{\"o}rr, Marcus and Parsa, Afshin and Aspelund, Thor and Demissie, Serkalem and Kathiresan, Sekar and Reilly, Muredach P and Taylor, Kent and Uitterlinden, Andre and Couper, David J and Sitzer, Matthias and K{\"a}h{\"o}nen, Mika and Illig, Thomas and Wild, Philipp S and Orr{\`u}, Marco and L{\"u}demann, Jan and Shuldiner, Alan R and Eiriksdottir, Gudny and White, Charles C and Rotter, Jerome I and Hofman, Albert and Seissler, Jochen and Zeller, Tanja and Usala, Gianluca and Ernst, Florian and Launer, Lenore J and D{\textquoteright}Agostino, Ralph B and O{\textquoteright}Leary, Daniel H and Ballantyne, Christie and Thiery, Joachim and Ziegler, Andreas and Lakatta, Edward G and Chilukoti, Ravi Kumar and Harris, Tamara B and Wolf, Philip A and Psaty, Bruce M and Polak, Joseph F and Li, Xia and Rathmann, Wolfgang and Uda, Manuela and Boerwinkle, Eric and Klopp, Norman and Schmidt, Helena and Wilson, James F and Viikari, Jorma and Koenig, Wolfgang and Blankenberg, Stefan and Newman, Anne B and Witteman, Jacqueline and Heiss, Gerardo and Duijn, Cornelia van and Scuteri, Angelo and Homuth, Georg and Mitchell, Braxton D and Gudnason, Vilmundur and O{\textquoteright}Donnell, Christopher J} } @article {6108, title = {Ischemic stroke is associated with the ABO locus: the EuroCLOT study.}, journal = {Ann Neurol}, volume = {73}, year = {2013}, month = {2013 Jan}, pages = {16-31}, abstract = {

OBJECTIVE: End-stage coagulation and the structure/function of fibrin are implicated in the pathogenesis of ischemic stroke. We explored whether genetic variants associated with end-stage coagulation in healthy volunteers account for the genetic predisposition to ischemic stroke and examined their influence on stroke subtype.

METHODS: Common genetic variants identified through genome-wide association studies of coagulation factors and fibrin structure/function in healthy twins (n = 2,100, Stage 1) were examined in ischemic stroke (n = 4,200 cases) using 2 independent samples of European ancestry (Stage 2). A third clinical collection having stroke subtyping (total 8,900 cases, 55,000 controls) was used for replication (Stage 3).

RESULTS: Stage 1 identified 524 single nucleotide polymorphisms (SNPs) from 23 linkage disequilibrium blocks having significant association (p < 5 {\texttimes} 10(-8)) with 1 or more coagulation/fibrin phenotypes. The most striking associations included SNP rs5985 with factor XIII activity (p = 2.6 {\texttimes} 10(-186)), rs10665 with FVII (p = 2.4 {\texttimes} 10(-47)), and rs505922 in the ABO gene with both von Willebrand factor (p = 4.7 {\texttimes} 10(-57)) and factor VIII (p = 1.2 {\texttimes} 10(-36)). In Stage 2, the 23 independent SNPs were examined in stroke cases/noncases using MOnica Risk, Genetics, Archiving and Monograph (MORGAM) and Wellcome Trust Case Control Consortium 2 collections. SNP rs505922 was nominally associated with ischemic stroke (odds ratio = 0.94, 95\% confidence interval = 0.88-0.99, p = 0.023). Independent replication in Meta-Stroke confirmed the rs505922 association with stroke, beta (standard error, SE) = 0.066 (0.02), p = 0.001, a finding specific to large-vessel and cardioembolic stroke (p = 0.001 and p = < 0.001, respectively) but not seen with small-vessel stroke (p = 0.811).

INTERPRETATION: ABO gene variants are associated with large-vessel and cardioembolic stroke but not small-vessel disease. This work sheds light on the different pathogenic mechanisms underpinning stroke subtype.

}, keywords = {ABO Blood-Group System, Adolescent, Adult, Aged, Aged, 80 and over, Blood Coagulation, Brain Ischemia, Cohort Studies, Europe, Female, Genetic Loci, Genetic Predisposition to Disease, Genetic Variation, Genome-Wide Association Study, Humans, Male, Middle Aged, Polymorphism, Single Nucleotide, Stroke, Young Adult}, issn = {1531-8249}, doi = {10.1002/ana.23838}, author = {Williams, Frances M K and Carter, Angela M and Hysi, Pirro G and Surdulescu, Gabriela and Hodgkiss, Dylan and Soranzo, Nicole and Traylor, Matthew and Bevan, Steve and Dichgans, Martin and Rothwell, Peter M W and Sudlow, Cathie and Farrall, Martin and Silander, Kaisa and Kaunisto, Mari and Wagner, Peter and Saarela, Olli and Kuulasmaa, Kari and Virtamo, Jarmo and Salomaa, Veikko and Amouyel, Philippe and Arveiler, Dominique and Ferrieres, Jean and Wiklund, Per-Gunnar and Ikram, M Arfan and Hofman, Albert and Boncoraglio, Giorgio B and Parati, Eugenio A and Helgadottir, Anna and Gretarsdottir, Solveig and Thorsteinsdottir, Unnur and Thorleifsson, Gudmar and Stefansson, Kari and Seshadri, Sudha and DeStefano, Anita and Gschwendtner, Andreas and Psaty, Bruce and Longstreth, Will and Mitchell, Braxton D and Cheng, Yu-Ching and Clarke, Robert and Ferrario, Marco and Bis, Joshua C and Levi, Christopher and Attia, John and Holliday, Elizabeth G and Scott, Rodney J and Fornage, Myriam and Sharma, Pankaj and Furie, Karen L and Rosand, Jonathan and Nalls, Mike and Meschia, James and Mosely, Thomas H and Evans, Alun and Palotie, Aarno and Markus, Hugh S and Grant, Peter J and Spector, Tim D} } @article {6155, title = {Multiethnic meta-analysis of genome-wide association studies in >100 000 subjects identifies 23 fibrinogen-associated Loci but no strong evidence of a causal association between circulating fibrinogen and cardiovascular disease.}, journal = {Circulation}, volume = {128}, year = {2013}, month = {2013 Sep 17}, pages = {1310-24}, abstract = {

BACKGROUND: Estimates of the heritability of plasma fibrinogen concentration, an established predictor of cardiovascular disease, range from 34\% to 50\%. Genetic variants so far identified by genome-wide association studies explain only a small proportion (<2\%) of its variation.

METHODS AND RESULTS: We conducted a meta-analysis of 28 genome-wide association studies including >90 000 subjects of European ancestry, the first genome-wide association meta-analysis of fibrinogen levels in 7 studies in blacks totaling 8289 samples, and a genome-wide association study in Hispanics totaling 1366 samples. Evaluation for association of single-nucleotide polymorphisms with clinical outcomes included a total of 40 695 cases and 85 582 controls for coronary artery disease, 4752 cases and 24 030 controls for stroke, and 3208 cases and 46 167 controls for venous thromboembolism. Overall, we identified 24 genome-wide significant (P<5{\texttimes}10(-8)) independent signals in 23 loci, including 15 novel associations, together accounting for 3.7\% of plasma fibrinogen variation. Gene-set enrichment analysis highlighted key roles in fibrinogen regulation for the 3 structural fibrinogen genes and pathways related to inflammation, adipocytokines, and thyrotrophin-releasing hormone signaling. Whereas lead single-nucleotide polymorphisms in a few loci were significantly associated with coronary artery disease, the combined effect of all 24 fibrinogen-associated lead single-nucleotide polymorphisms was not significant for coronary artery disease, stroke, or venous thromboembolism.

CONCLUSIONS: We identify 23 robustly associated fibrinogen loci, 15 of which are new. Clinical outcome analysis of these loci does not support a causal relationship between circulating levels of fibrinogen and coronary artery disease, stroke, or venous thromboembolism.

}, keywords = {Adolescent, Adult, African Continental Ancestry Group, Aged, Aged, 80 and over, Cardiovascular Diseases, Coronary Artery Disease, European Continental Ancestry Group, Female, Fibrinogen, Genetic Loci, Genetic Predisposition to Disease, Genome-Wide Association Study, Hispanic Americans, Humans, Male, Middle Aged, Myocardial Infarction, Polymorphism, Single Nucleotide, Risk Factors, Stroke, Venous Thromboembolism, Young Adult}, issn = {1524-4539}, doi = {10.1161/CIRCULATIONAHA.113.002251}, author = {Sabater-Lleal, Maria and Huang, Jie and Chasman, Daniel and Naitza, Silvia and Dehghan, Abbas and Johnson, Andrew D and Teumer, Alexander and Reiner, Alex P and Folkersen, Lasse and Basu, Saonli and Rudnicka, Alicja R and Trompet, Stella and M{\"a}larstig, Anders and Baumert, Jens and Bis, Joshua C and Guo, Xiuqing and Hottenga, Jouke J and Shin, So-Youn and Lopez, Lorna M and Lahti, Jari and Tanaka, Toshiko and Yanek, Lisa R and Oudot-Mellakh, Tiphaine and Wilson, James F and Navarro, Pau and Huffman, Jennifer E and Zemunik, Tatijana and Redline, Susan and Mehra, Reena and Pulanic, Drazen and Rudan, Igor and Wright, Alan F and Kolcic, Ivana and Polasek, Ozren and Wild, Sarah H and Campbell, Harry and Curb, J David and Wallace, Robert and Liu, Simin and Eaton, Charles B and Becker, Diane M and Becker, Lewis C and Bandinelli, Stefania and R{\"a}ikk{\"o}nen, Katri and Widen, Elisabeth and Palotie, Aarno and Fornage, Myriam and Green, David and Gross, Myron and Davies, Gail and Harris, Sarah E and Liewald, David C and Starr, John M and Williams, Frances M K and Grant, Peter J and Spector, Timothy D and Strawbridge, Rona J and Silveira, Angela and Sennblad, Bengt and Rivadeneira, Fernando and Uitterlinden, Andr{\'e} G and Franco, Oscar H and Hofman, Albert and van Dongen, Jenny and Willemsen, Gonneke and Boomsma, Dorret I and Yao, Jie and Swords Jenny, Nancy and Haritunians, Talin and McKnight, Barbara and Lumley, Thomas and Taylor, Kent D and Rotter, Jerome I and Psaty, Bruce M and Peters, Annette and Gieger, Christian and Illig, Thomas and Grotevendt, Anne and Homuth, Georg and V{\"o}lzke, Henry and Kocher, Thomas and Goel, Anuj and Franzosi, Maria Grazia and Seedorf, Udo and Clarke, Robert and Steri, Maristella and Tarasov, Kirill V and Sanna, Serena and Schlessinger, David and Stott, David J and Sattar, Naveed and Buckley, Brendan M and Rumley, Ann and Lowe, Gordon D and McArdle, Wendy L and Chen, Ming-Huei and Tofler, Geoffrey H and Song, Jaejoon and Boerwinkle, Eric and Folsom, Aaron R and Rose, Lynda M and Franco-Cereceda, Anders and Teichert, Martina and Ikram, M Arfan and Mosley, Thomas H and Bevan, Steve and Dichgans, Martin and Rothwell, Peter M and Sudlow, Cathie L M and Hopewell, Jemma C and Chambers, John C and Saleheen, Danish and Kooner, Jaspal S and Danesh, John and Nelson, Christopher P and Erdmann, Jeanette and Reilly, Muredach P and Kathiresan, Sekar and Schunkert, Heribert and Morange, Pierre-Emmanuel and Ferrucci, Luigi and Eriksson, Johan G and Jacobs, David and Deary, Ian J and Soranzo, Nicole and Witteman, Jacqueline C M and de Geus, Eco J C and Tracy, Russell P and Hayward, Caroline and Koenig, Wolfgang and Cucca, Francesco and Jukema, J Wouter and Eriksson, Per and Seshadri, Sudha and Markus, Hugh S and Watkins, Hugh and Samani, Nilesh J and Wallaschofski, Henri and Smith, Nicholas L and Tregouet, David and Ridker, Paul M and Tang, Weihong and Strachan, David P and Hamsten, Anders and O{\textquoteright}Donnell, Christopher J} } @article {6574, title = {Meta-analysis in more than 17,900 cases of ischemic stroke reveals a novel association at 12q24.12.}, journal = {Neurology}, volume = {83}, year = {2014}, month = {2014 Aug 19}, pages = {678-85}, abstract = {

OBJECTIVES: To perform a genome-wide association study (GWAS) using the Immunochip array in 3,420 cases of ischemic stroke and 6,821 controls, followed by a meta-analysis with data from more than 14,000 additional ischemic stroke cases.

METHODS: Using the Immunochip, we genotyped 3,420 ischemic stroke cases and 6,821 controls. After imputation we meta-analyzed the results with imputed GWAS data from 3,548 cases and 5,972 controls recruited from the ischemic stroke WTCCC2 study, and with summary statistics from a further 8,480 cases and 56,032 controls in the METASTROKE consortium. A final in silico "look-up" of 2 single nucleotide polymorphisms in 2,522 cases and 1,899 controls was performed. Associations were also examined in 1,088 cases with intracerebral hemorrhage and 1,102 controls.

RESULTS: In an overall analysis of 17,970 cases of ischemic stroke and 70,764 controls, we identified a novel association on chromosome 12q24 (rs10744777, odds ratio [OR] 1.10 [1.07-1.13], p = 7.12 {\texttimes} 10(-11)) with ischemic stroke. The association was with all ischemic stroke rather than an individual stroke subtype, with similar effect sizes seen in different stroke subtypes. There was no association with intracerebral hemorrhage (OR 1.03 [0.90-1.17], p = 0.695).

CONCLUSION: Our results show, for the first time, a genetic risk locus associated with ischemic stroke as a whole, rather than in a subtype-specific manner. This finding was not associated with intracerebral hemorrhage.

}, keywords = {Brain Ischemia, Cerebral Hemorrhage, Chromosomes, Human, Pair 12, Genetic Predisposition to Disease, Genome-Wide Association Study, Genotype, Humans, Polymorphism, Single Nucleotide, Risk, Stroke}, issn = {1526-632X}, doi = {10.1212/WNL.0000000000000707}, author = {Kilarski, Laura L and Achterberg, Sefanja and Devan, William J and Traylor, Matthew and Malik, Rainer and Lindgren, Arne and Pare, Guillame and Sharma, Pankaj and Slowik, Agniesczka and Thijs, Vincent and Walters, Matthew and Worrall, Bradford B and Sale, Mich{\`e}le M and Algra, Ale and Kappelle, L Jaap and Wijmenga, Cisca and Norrving, Bo and Sandling, Johanna K and R{\"o}nnblom, Lars and Goris, An and Franke, Andre and Sudlow, Cathie and Rothwell, Peter M and Levi, Christopher and Holliday, Elizabeth G and Fornage, Myriam and Psaty, Bruce and Gretarsdottir, Solveig and Thorsteinsdottir, Unnar and Seshadri, Sudha and Mitchell, Braxton D and Kittner, Steven and Clarke, Robert and Hopewell, Jemma C and Bis, Joshua C and Boncoraglio, Giorgio B and Meschia, James and Ikram, M Arfan and Hansen, Bjorn M and Montaner, Joan and Thorleifsson, Gudmar and Stefanson, Kari and Rosand, Jonathan and de Bakker, Paul I W and Farrall, Martin and Dichgans, Martin and Markus, Hugh S and Bevan, Steve} } @article {6297, title = {Multilocus genetic risk score associates with ischemic stroke in case-control and prospective cohort studies.}, journal = {Stroke}, volume = {45}, year = {2014}, month = {2014 Feb}, pages = {394-402}, abstract = {

BACKGROUND AND PURPOSE: Genome-wide association studies have revealed multiple common variants associated with known risk factors for ischemic stroke (IS). However, their aggregate effect on risk is uncertain. We aimed to generate a multilocus genetic risk score (GRS) for IS based on genome-wide association studies data from clinical-based samples and to establish its external validity in prospective population-based cohorts.

METHODS: Three thousand five hundred forty-eight clinic-based IS cases and 6399 controls from the Wellcome Trust Case Control Consortium 2 were used for derivation of the GRS. Subjects from the METASTROKE consortium served as a replication sample. The validation sample consisted of 22 751 participants from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium. We selected variants that had reached genome-wide significance in previous association studies on established risk factors for IS.

RESULTS: A combined GRS for atrial fibrillation, coronary artery disease, hypertension, and systolic blood pressure significantly associated with IS both in the case-control samples and in the prospective population-based studies. Subjects in the top quintile of the combined GRS had >2-fold increased risk of IS compared with subjects in the lowest quintile. Addition of the combined GRS to a simple model based on sex significantly improved the prediction of IS in the combined clinic-based samples but not in the population-based studies, and there was no significant improvement in net reclassification.

CONCLUSIONS: A multilocus GRS based on common variants for established cardiovascular risk factors was significantly associated with IS both in clinic-based samples and in the general population. However, the improvement in clinical risk prediction was found to be small.

}, keywords = {Adult, Aged, Aged, 80 and over, Atrial Fibrillation, Blood Pressure, Brain Ischemia, Case-Control Studies, Cohort Studies, Coronary Artery Disease, Female, Genetic Predisposition to Disease, Genetic Variation, Genome-Wide Association Study, Humans, Hypertension, Male, Middle Aged, Multilocus Sequence Typing, Polymorphism, Single Nucleotide, Population, Prospective Studies, Reproducibility of Results, Risk Assessment, Risk Factors, Sex Factors, Stroke}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.113.002938}, author = {Malik, Rainer and Bevan, Steve and Nalls, Michael A and Holliday, Elizabeth G and Devan, William J and Cheng, Yu-Ching and Ibrahim-Verbaas, Carla A and Verhaaren, Benjamin F J and Bis, Joshua C and Joon, Aron Y and de Stefano, Anita L and Fornage, Myriam and Psaty, Bruce M and Ikram, M Arfan and Launer, Lenore J and van Duijn, Cornelia M and Sharma, Pankaj and Mitchell, Braxton D and Rosand, Jonathan and Meschia, James F and Levi, Christopher and Rothwell, Peter M and Sudlow, Cathie and Markus, Hugh S and Seshadri, Sudha and Dichgans, Martin} } @article {6864, title = {Common variation in COL4A1/COL4A2 is associated with sporadic cerebral small vessel disease.}, journal = {Neurology}, volume = {84}, year = {2015}, month = {2015 Mar 3}, pages = {918-26}, abstract = {

OBJECTIVES: We hypothesized that common variants in the collagen genes COL4A1/COL4A2 are associated with sporadic forms of cerebral small vessel disease.

METHODS: We conducted meta-analyses of existing genotype data among individuals of European ancestry to determine associations of 1,070 common single nucleotide polymorphisms (SNPs) in the COL4A1/COL4A2 genomic region with the following: intracerebral hemorrhage and its subtypes (deep, lobar) (1,545 cases, 1,485 controls); ischemic stroke and its subtypes (cardioembolic, large vessel disease, lacunar) (12,389 cases, 62,004 controls); and white matter hyperintensities (2,733 individuals with ischemic stroke and 9,361 from population-based cohorts with brain MRI data). We calculated a statistical significance threshold that accounted for multiple testing and linkage disequilibrium between SNPs (p < 0.000084).

RESULTS: Three intronic SNPs in COL4A2 were significantly associated with deep intracerebral hemorrhage (lead SNP odds ratio [OR] 1.29, 95\% confidence interval [CI] 1.14-1.46, p = 0.00003; r(2) > 0.9 between SNPs). Although SNPs associated with deep intracerebral hemorrhage did not reach our significance threshold for association with lacunar ischemic stroke (lead SNP OR 1.10, 95\% CI 1.03-1.18, p = 0.0073), and with white matter hyperintensity volume in symptomatic ischemic stroke patients (lead SNP OR 1.07, 95\% CI 1.01-1.13, p = 0.016), the direction of association was the same. There was no convincing evidence of association with white matter hyperintensities in population-based studies or with non-small vessel disease cerebrovascular phenotypes.

CONCLUSIONS: Our results indicate an association between common variation in the COL4A2 gene and symptomatic small vessel disease, particularly deep intracerebral hemorrhage. These findings merit replication studies, including in ethnic groups of non-European ancestry.

}, keywords = {Cerebral Small Vessel Diseases, Collagen Type IV, Genetic Association Studies, Genetic Variation, Humans, Polymorphism, Single Nucleotide}, issn = {1526-632X}, doi = {10.1212/WNL.0000000000001309}, author = {Rannikmae, Kristiina and Davies, Gail and Thomson, Pippa A and Bevan, Steve and Devan, William J and Falcone, Guido J and Traylor, Matthew and Anderson, Christopher D and Battey, Thomas W K and Radmanesh, Farid and Deka, Ranjan and Woo, Jessica G and Martin, Lisa J and Jimenez-Conde, Jordi and Selim, Magdy and Brown, Devin L and Silliman, Scott L and Kidwell, Chelsea S and Montaner, Joan and Langefeld, Carl D and Slowik, Agnieszka and Hansen, Bjorn M and Lindgren, Arne G and Meschia, James F and Fornage, Myriam and Bis, Joshua C and Debette, Stephanie and Ikram, Mohammad A and Longstreth, Will T and Schmidt, Reinhold and Zhang, Cathy R and Yang, Qiong and Sharma, Pankaj and Kittner, Steven J and Mitchell, Braxton D and Holliday, Elizabeth G and Levi, Christopher R and Attia, John and Rothwell, Peter M and Poole, Deborah L and Boncoraglio, Giorgio B and Psaty, Bruce M and Malik, Rainer and Rost, Natalia and Worrall, Bradford B and Dichgans, Martin and Van Agtmael, Tom and Woo, Daniel and Markus, Hugh S and Seshadri, Sudha and Rosand, Jonathan and Sudlow, Cathie L M} } @article {6688, title = {Genetic overlap between diagnostic subtypes of ischemic stroke.}, journal = {Stroke}, volume = {46}, year = {2015}, month = {2015 Mar}, pages = {615-9}, abstract = {

BACKGROUND AND PURPOSE: Despite moderate heritability, the phenotypic heterogeneity of ischemic stroke has hampered gene discovery, motivating analyses of diagnostic subtypes with reduced sample sizes. We assessed evidence for a shared genetic basis among the 3 major subtypes: large artery atherosclerosis (LAA), cardioembolism, and small vessel disease (SVD), to inform potential cross-subtype analyses.

METHODS: Analyses used genome-wide summary data for 12 389 ischemic stroke cases (including 2167 LAA, 2405 cardioembolism, and 1854 SVD) and 62 004 controls from the Metastroke consortium. For 4561 cases and 7094 controls, individual-level genotype data were also available. Genetic correlations between subtypes were estimated using linear mixed models and polygenic profile scores. Meta-analysis of a combined LAA-SVD phenotype (4021 cases and 51 976 controls) was performed to identify shared risk alleles.

RESULTS: High genetic correlation was identified between LAA and SVD using linear mixed models (rg=0.96, SE=0.47, P=9{\texttimes}10(-4)) and profile scores (rg=0.72; 95\% confidence interval, 0.52-0.93). Between LAA and cardioembolism and SVD and cardioembolism, correlation was moderate using linear mixed models but not significantly different from zero for profile scoring. Joint meta-analysis of LAA and SVD identified strong association (P=1{\texttimes}10(-7)) for single nucleotide polymorphisms near the opioid receptor μ1 (OPRM1) gene.

CONCLUSIONS: Our results suggest that LAA and SVD, which have been hitherto treated as genetically distinct, may share a substantial genetic component. Combined analyses of LAA and SVD may increase power to identify small-effect alleles influencing shared pathophysiological processes.

}, keywords = {Alleles, Atherosclerosis, Cerebral Small Vessel Diseases, Cohort Studies, Data Interpretation, Statistical, Embolism, Genome-Wide Association Study, Genotype, Humans, Ischemia, Linear Models, Meta-Analysis as Topic, Phenotype, Polymorphism, Single Nucleotide, Stroke}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.114.007930}, author = {Holliday, Elizabeth G and Traylor, Matthew and Malik, Rainer and Bevan, Steve and Falcone, Guido and Hopewell, Jemma C and Cheng, Yu-Ching and Cotlarciuc, Ioana and Bis, Joshua C and Boerwinkle, Eric and Boncoraglio, Giorgio B and Clarke, Robert and Cole, John W and Fornage, Myriam and Furie, Karen L and Ikram, M Arfan and Jannes, Jim and Kittner, Steven J and Lincz, Lisa F and Maguire, Jane M and Meschia, James F and Mosley, Thomas H and Nalls, Mike A and Oldmeadow, Christopher and Parati, Eugenio A and Psaty, Bruce M and Rothwell, Peter M and Seshadri, Sudha and Scott, Rodney J and Sharma, Pankaj and Sudlow, Cathie and Wiggins, Kerri L and Worrall, Bradford B and Rosand, Jonathan and Mitchell, Braxton D and Dichgans, Martin and Markus, Hugh S and Levi, Christopher and Attia, John and Wray, Naomi R} } @article {6991, title = {Genome-Wide Association Analysis of Young-Onset Stroke Identifies a Locus on Chromosome 10q25 Near HABP2.}, journal = {Stroke}, volume = {47}, year = {2016}, month = {2016 Feb}, pages = {307-16}, abstract = {

BACKGROUND AND PURPOSE: Although a genetic contribution to ischemic stroke is well recognized, only a handful of stroke loci have been identified by large-scale genetic association studies to date. Hypothesizing that genetic effects might be stronger for early- versus late-onset stroke, we conducted a 2-stage meta-analysis of genome-wide association studies, focusing on stroke cases with an age of onset <60 years.

METHODS: The discovery stage of our genome-wide association studies included 4505 cases and 21 968 controls of European, South-Asian, and African ancestry, drawn from 6 studies. In Stage 2, we selected the lead genetic variants at loci with association P<5{\texttimes}10(-6) and performed in silico association analyses in an independent sample of <=1003 cases and 7745 controls.

RESULTS: One stroke susceptibility locus at 10q25 reached genome-wide significance in the combined analysis of all samples from the discovery and follow-up stages (rs11196288; odds ratio =1.41; P=9.5{\texttimes}10(-9)). The associated locus is in an intergenic region between TCF7L2 and HABP2. In a further analysis in an independent sample, we found that 2 single nucleotide polymorphisms in high linkage disequilibrium with rs11196288 were significantly associated with total plasma factor VII-activating protease levels, a product of HABP2.

CONCLUSIONS: HABP2, which encodes an extracellular serine protease involved in coagulation, fibrinolysis, and inflammatory pathways, may be a genetic susceptibility locus for early-onset stroke.

}, keywords = {Adult, African Continental Ancestry Group, Age of Onset, Aged, Asian Continental Ancestry Group, Brain Ischemia, Chromosomes, Human, Pair 10, Computer Simulation, DNA, Intergenic, European Continental Ancestry Group, Female, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Male, Middle Aged, Odds Ratio, Polymorphism, Single Nucleotide, Serine Endopeptidases, Stroke}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.115.011328}, author = {Cheng, Yu-Ching and Stanne, Tara M and Giese, Anne-Katrin and Ho, Weang Kee and Traylor, Matthew and Amouyel, Philippe and Holliday, Elizabeth G and Malik, Rainer and Xu, Huichun and Kittner, Steven J and Cole, John W and O{\textquoteright}Connell, Jeffrey R and Danesh, John and Rasheed, Asif and Zhao, Wei and Engelter, Stefan and Grond-Ginsbach, Caspar and Kamatani, Yoichiro and Lathrop, Mark and Leys, Didier and Thijs, Vincent and Metso, Tiina M and Tatlisumak, Turgut and Pezzini, Alessandro and Parati, Eugenio A and Norrving, Bo and Bevan, Steve and Rothwell, Peter M and Sudlow, Cathie and Slowik, Agnieszka and Lindgren, Arne and Walters, Matthew R and Jannes, Jim and Shen, Jess and Crosslin, David and Doheny, Kimberly and Laurie, Cathy C and Kanse, Sandip M and Bis, Joshua C and Fornage, Myriam and Mosley, Thomas H and Hopewell, Jemma C and Strauch, Konstantin and M{\"u}ller-Nurasyid, Martina and Gieger, Christian and Waldenberger, Melanie and Peters, Annette and Meisinger, Christine and Ikram, M Arfan and Longstreth, W T and Meschia, James F and Seshadri, Sudha and Sharma, Pankaj and Worrall, Bradford and Jern, Christina and Levi, Christopher and Dichgans, Martin and Boncoraglio, Giorgio B and Markus, Hugh S and Debette, Stephanie and Rolfs, Arndt and Saleheen, Danish and Mitchell, Braxton D} }