Browsing by Subject "Intracranial Aneurysm"

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    Exome-chip association analysis of intracranial aneurysms
    (American Academy of Neurology, 2020-02-04) van 't Hof, Femke N.G.; Lai, Dongbing; van Setten, Jessica; Bots, Michiel L.; Vaartjes, Ilonca; Broderick, Joseph; Woo, Daniel; Foroud, Tatiana; Rinkel, Gabriel J.E.; de Bakker, Paul I.W.; Ruigrok, Ynte M.; Medical and Molecular Genetics, School of Medicine
    Objective: To investigate to what extent low-frequency genetic variants (with minor allele frequencies <5%) affect the risk of intracranial aneurysms (IAs). Methods: One thousand fifty-six patients with IA and 2,097 population-based controls from the Netherlands were genotyped with the Illumina HumanExome BeadChip. After quality control (QC) of samples and single nucleotide variants (SNVs), we conducted a single variant analysis using the Fisher exact test. We also performed the variable threshold (VT) test and the sequence kernel association test (SKAT) at different minor allele count (MAC) thresholds of >5 and >0 to test the hypothesis that multiple variants within the same gene are associated with IA risk. Significant results were tested in a replication cohort of 425 patients with IA and 311 controls, and results of the 2 cohorts were combined in a meta-analysis. Results: After QC, 995 patients with IA and 2,080 controls remained for further analysis. The single variant analysis comprising 46,534 SNVs did not identify significant loci at the genome-wide level. The gene-based tests showed a statistically significant association for fibulin 2 (FBLN2) (best p = 1 × 10-6 for the VT test, MAC >5). Associations were not statistically significant in the independent but smaller replication cohort (p > 0.57) but became slightly stronger in a meta-analysis of the 2 cohorts (best p = 4.8 × 10-7 for the SKAT, MAC ≥1). Conclusion: Gene-based tests indicated an association for FBLN2, a gene encoding an extracellular matrix protein implicated in vascular wall remodeling, but independent validation in larger cohorts is warranted. We did not identify any significant associations for single low-frequency genetic variants.
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    Genome-wide association study of intracranial aneurysm identifies a new association on chromosome 7
    (Ovid Technologies Wolters Kluwer – American Heart Association, 2014-11) Foroud, Tatiana; Lai, Dongbing; Koller, Daniel; van’t Hof, Femke; Kurki, Mitja I.; Anderson, Craig S.; Brown, Robert D.; Connolly, E. Sander; Eriksson, Johan G.; Flaherty, Matthew; Fornage, Myriam; von und zuFraunberg, Mikael; Gaál, Emília I.; Laakso, Aki; Hernesniemi, Juha; Huston, John; Jääskeläinen, Juha E.; Kiemeney, Lambertus A.; Kivisaari, Riku; Kleindorfer, Dawn; Ko, Nerissa; Lehto, Hanna; Mackey, Jason; Meissner, Irene; Moomaw, Charles J.; Mosley, Thomas H.; Moskala, Marek; Niemelä, Mika; Palotie, Aarno; Pera, Joanna; Rinkel, Gabriel; Ripke, Stephan; Rouleau, Guy; Ruigrok, Ynte; Sauerbeck, Laura; Słowik, Agnieszka; Vermeulen, Sita H.; Woo, Daniel; Worrall, Bradford B.; Broderick, Joseph; Department of Medical & Molecular Genetics, IU School of Medicine
    BACKGROUND AND PURPOSE: Common variants have been identified using genome-wide association studies which contribute to intracranial aneurysms (IA) susceptibility. However, it is clear that the variants identified to date do not account for the estimated genetic contribution to disease risk. METHODS: Initial analysis was performed in a discovery sample of 2617 IA cases and 2548 controls of white ancestry. Novel chromosomal regions meeting genome-wide significance were further tested for association in 2 independent replication samples: Dutch (717 cases; 3004 controls) and Finnish (799 cases; 2317 controls). A meta-analysis was performed to combine the results from the 3 studies for key chromosomal regions of interest. RESULTS: Genome-wide evidence of association was detected in the discovery sample on chromosome 9 (CDKN2BAS; rs10733376: P<1.0×10(-11)), in a gene previously associated with IA. A novel region on chromosome 7, near HDAC9, was associated with IA (rs10230207; P=4.14×10(-8)). This association replicated in the Dutch sample (P=0.01) but failed to show association in the Finnish sample (P=0.25). Meta-analysis results of the 3 cohorts reached statistical significant (P=9.91×10(-10)). CONCLUSIONS: We detected a novel region associated with IA susceptibility that was replicated in an independent Dutch sample. This region on chromosome 7 has been previously associated with ischemic stroke and the large vessel stroke occlusive subtype (including HDAC9), suggesting a possible genetic link between this stroke subtype and IA.