@article {6367, title = {Genome-wide association study for circulating tissue plasminogen activator levels and functional follow-up implicates endothelial STXBP5 and STX2.}, journal = {Arterioscler Thromb Vasc Biol}, volume = {34}, year = {2014}, month = {2014 May}, pages = {1093-101}, abstract = {

OBJECTIVE: Tissue plasminogen activator (tPA), a serine protease, catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for endogenous fibrinolysis. In some populations, elevated plasma levels of tPA have been associated with myocardial infarction and other cardiovascular diseases. We conducted a meta-analysis of genome-wide association studies to identify novel correlates of circulating levels of tPA.

APPROACH AND RESULTS: Fourteen cohort studies with tPA measures (N=26 929) contributed to the meta-analysis. Three loci were significantly associated with circulating tPA levels (P<5.0{\texttimes}10(-8)). The first locus is on 6q24.3, with the lead single nucleotide polymorphism (SNP; rs9399599; P=2.9{\texttimes}10(-14)) within STXBP5. The second locus is on 8p11.21. The lead SNP (rs3136739; P=1.3{\texttimes}10(-9)) is intronic to POLB and <200 kb away from the tPA encoding the gene PLAT. We identified a nonsynonymous SNP (rs2020921) in modest linkage disequilibrium with rs3136739 (r(2)=0.50) within exon 5 of PLAT (P=2.0{\texttimes}10(-8)). The third locus is on 12q24.33, with the lead SNP (rs7301826; P=1.0{\texttimes}10(-9)) within intron 7 of STX2. We further found evidence for the association of lead SNPs in STXBP5 and STX2 with expression levels of the respective transcripts. In in vitro cell studies, silencing STXBP5 decreased the release of tPA from vascular endothelial cells, whereas silencing STX2 increased the tPA release. Through an in silico lookup, we found no associations of the 3 lead SNPs with coronary artery disease or stroke.

CONCLUSIONS: We identified 3 loci associated with circulating tPA levels, the PLAT region, STXBP5, and STX2. Our functional studies implicate a novel role for STXBP5 and STX2 in regulating tPA release.

}, keywords = {Aged, Cells, Cultured, Coronary Artery Disease, Endothelial Cells, Europe, Female, Gene Expression Regulation, Gene Silencing, Genetic Loci, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Male, Middle Aged, Nerve Tissue Proteins, Phenotype, Polymorphism, Single Nucleotide, R-SNARE Proteins, Risk Factors, Stroke, Syntaxin 1, Tissue Plasminogen Activator, Transfection, United States, Up-Regulation}, issn = {1524-4636}, doi = {10.1161/ATVBAHA.113.302088}, author = {Huang, Jie and Huffman, Jennifer E and Yamakuchi, Munekazu and Yamkauchi, Munekazu and Trompet, Stella and Asselbergs, Folkert W and Sabater-Lleal, Maria and Tr{\'e}gou{\"e}t, David-Alexandre and Chen, Wei-Min and Smith, Nicholas L and Kleber, Marcus E and Shin, So-Youn and Becker, Diane M and Tang, Weihong and Dehghan, Abbas and Johnson, Andrew D and Truong, Vinh and Folkersen, Lasse and Yang, Qiong and Oudot-Mellkah, Tiphaine and Buckley, Brendan M and Moore, Jason H and Williams, Frances M K and Campbell, Harry and Silbernagel, G{\"u}nther and Vitart, Veronique and Rudan, Igor and Tofler, Geoffrey H and Navis, Gerjan J and DeStefano, Anita and Wright, Alan F and Chen, Ming-Huei and de Craen, Anton J M and Worrall, Bradford B and Rudnicka, Alicja R and Rumley, Ann and Bookman, Ebony B and Psaty, Bruce M and Chen, Fang and Keene, Keith L and Franco, Oscar H and B{\"o}hm, Bernhard O and Uitterlinden, Andr{\'e} G and Carter, Angela M and Jukema, J Wouter and Sattar, Naveed and Bis, Joshua C and Ikram, Mohammad A and Sale, Mich{\`e}le M and McKnight, Barbara and Fornage, Myriam and Ford, Ian and Taylor, Kent and Slagboom, P Eline and McArdle, Wendy L and Hsu, Fang-Chi and Franco-Cereceda, Anders and Goodall, Alison H and Yanek, Lisa R and Furie, Karen L and Cushman, Mary and Hofman, Albert and Witteman, Jacqueline C M and Folsom, Aaron R and Basu, Saonli and Matijevic, Nena and van Gilst, Wiek H and Wilson, James F and Westendorp, Rudi G J and Kathiresan, Sekar and Reilly, Muredach P and Tracy, Russell P and Polasek, Ozren and Winkelmann, Bernhard R and Grant, Peter J and Hillege, Hans L and Cambien, Francois and Stott, David J and Lowe, Gordon D and Spector, Timothy D and Meigs, James B and M{\"a}rz, Winfried and Eriksson, Per and Becker, Lewis C and Morange, Pierre-Emmanuel and Soranzo, Nicole and Williams, Scott M and Hayward, Caroline and van der Harst, Pim and Hamsten, Anders and Lowenstein, Charles J and Strachan, David P and O{\textquoteright}Donnell, Christopher J} } @article {6788, title = {Rare and low-frequency variants and their association with plasma levels of fibrinogen, FVII, FVIII, and vWF.}, journal = {Blood}, volume = {126}, year = {2015}, month = {2015 Sep 10}, pages = {e19-29}, abstract = {

Fibrinogen, coagulation factor VII (FVII), and factor VIII (FVIII) and its carrier von Willebrand factor (vWF) play key roles in hemostasis. Previously identified common variants explain only a small fraction of the trait heritabilities, and additional variations may be explained by associations with rarer variants with larger effects. The aim of this study was to identify low-frequency (minor allele frequency [MAF] >=0.01 and <0.05) and rare (MAF <0.01) variants that influence plasma concentrations of these 4 hemostatic factors by meta-analyzing exome chip data from up to 76,000 participants of 4 ancestries. We identified 12 novel associations of low-frequency (n = 2) and rare (n = 10) variants across the fibrinogen, FVII, FVIII, and vWF traits that were independent of previously identified associations. Novel loci were found within previously reported genes and had effect sizes much larger than and independent of previously identified common variants. In addition, associations at KCNT1, HID1, and KATNB1 identified new candidate genes related to hemostasis for follow-up replication and functional genomic analysis. Newly identified low-frequency and rare-variant associations accounted for modest amounts of trait variance and therefore are unlikely to increase predicted trait heritability but provide new information for understanding individual variation in hemostasis pathways.

}, keywords = {Cohort Studies, Factor VII, Factor VIII, Fibrinogen, Gene Frequency, Genetic Association Studies, Genetic Variation, Humans, Nerve Tissue Proteins, Polymorphism, Single Nucleotide, Potassium Channels, von Willebrand Factor}, issn = {1528-0020}, doi = {10.1182/blood-2015-02-624551}, author = {Huffman, Jennifer E and de Vries, Paul S and Morrison, Alanna C and Sabater-Lleal, Maria and Kacprowski, Tim and Auer, Paul L and Brody, Jennifer A and Chasman, Daniel I and Chen, Ming-Huei and Guo, Xiuqing and Lin, Li-An and Marioni, Riccardo E and M{\"u}ller-Nurasyid, Martina and Yanek, Lisa R and Pankratz, Nathan and Grove, Megan L and de Maat, Moniek P M and Cushman, Mary and Wiggins, Kerri L and Qi, Lihong and Sennblad, Bengt and Harris, Sarah E and Polasek, Ozren and Riess, Helene and Rivadeneira, Fernando and Rose, Lynda M and Goel, Anuj and Taylor, Kent D and Teumer, Alexander and Uitterlinden, Andr{\'e} G and Vaidya, Dhananjay and Yao, Jie and Tang, Weihong and Levy, Daniel and Waldenberger, Melanie and Becker, Diane M and Folsom, Aaron R and Giulianini, Franco and Greinacher, Andreas and Hofman, Albert and Huang, Chiang-Ching and Kooperberg, Charles and Silveira, Angela and Starr, John M and Strauch, Konstantin and Strawbridge, Rona J and Wright, Alan F and McKnight, Barbara and Franco, Oscar H and Zakai, Neil and Mathias, Rasika A and Psaty, Bruce M and Ridker, Paul M and Tofler, Geoffrey H and V{\"o}lker, Uwe and Watkins, Hugh and Fornage, Myriam and Hamsten, Anders and Deary, Ian J and Boerwinkle, Eric and Koenig, Wolfgang and Rotter, Jerome I and Hayward, Caroline and Dehghan, Abbas and Reiner, Alex P and O{\textquoteright}Donnell, Christopher J and Smith, Nicholas L} }