@article {6284, title = {Common genetic loci influencing plasma homocysteine concentrations and their effect on risk of coronary artery disease.}, journal = {Am J Clin Nutr}, volume = {98}, year = {2013}, month = {2013 Sep}, pages = {668-76}, abstract = {

BACKGROUND: The strong observational association between total homocysteine (tHcy) concentrations and risk of coronary artery disease (CAD) and the null associations in the homocysteine-lowering trials have prompted the need to identify genetic variants associated with homocysteine concentrations and risk of CAD.

OBJECTIVE: We tested whether common genetic polymorphisms associated with variation in tHcy are also associated with CAD.

DESIGN: We conducted a meta-analysis of genome-wide association studies (GWAS) on tHcy concentrations in 44,147 individuals of European descent. Polymorphisms associated with tHcy (P < 10($^{-}$$^{8}$) were tested for association with CAD in 31,400 cases and 92,927 controls.

RESULTS: Common variants at 13 loci, explaining 5.9\% of the variation in tHcy, were associated with tHcy concentrations, including 6 novel loci in or near MMACHC (2.1 {\texttimes} 10$^{-}$$^{9}$), SLC17A3 (1.0 {\texttimes} 10$^{-}$$^{8}$), GTPB10 (1.7 {\texttimes} 10$^{-}$$^{8}$), CUBN (7.5 {\texttimes} 10$^{-}${\textonesuperior}$^{0}$), HNF1A (1.2 {\texttimes} 10$^{-}${\textonesuperior}{\texttwosuperior})), and FUT2 (6.6 {\texttimes} 10$^{-}$$^{9}$), and variants previously reported at or near the MTHFR, MTR, CPS1, MUT, NOX4, DPEP1, and CBS genes. Individuals within the highest 10\% of the genotype risk score (GRS) had 3-μmol/L higher mean tHcy concentrations than did those within the lowest 10\% of the GRS (P = 1 {\texttimes} 10$^{-}${\textthreesuperior}$^{6}$). The GRS was not associated with risk of CAD (OR: 1.01; 95\% CI: 0.98, 1.04; P = 0.49).

CONCLUSIONS: We identified several novel loci that influence plasma tHcy concentrations. Overall, common genetic variants that influence plasma tHcy concentrations are not associated with risk of CAD in white populations, which further refutes the causal relevance of moderately elevated tHcy concentrations and tHcy-related pathways for CAD.

}, keywords = {Coronary Artery Disease, Genes, Genetic Loci, Genetic Predisposition to Disease, Genotype, Homocysteine, Humans, Polymorphism, Genetic, Risk Factors}, issn = {1938-3207}, doi = {10.3945/ajcn.112.044545}, author = {van Meurs, Joyce B J and Par{\'e}, Guillaume and Schwartz, Stephen M and Hazra, Aditi and Tanaka, Toshiko and Vermeulen, Sita H and Cotlarciuc, Ioana and Yuan, Xin and M{\"a}larstig, Anders and Bandinelli, Stefania and Bis, Joshua C and Blom, Henk and Brown, Morris J and Chen, Constance and Chen, Yii-Der and Clarke, Robert J and Dehghan, Abbas and Erdmann, Jeanette and Ferrucci, Luigi and Hamsten, Anders and Hofman, Albert and Hunter, David J and Goel, Anuj and Johnson, Andrew D and Kathiresan, Sekar and Kampman, Ellen and Kiel, Douglas P and Kiemeney, Lambertus A L M and Chambers, John C and Kraft, Peter and Lindemans, Jan and McKnight, Barbara and Nelson, Christopher P and O{\textquoteright}Donnell, Christopher J and Psaty, Bruce M and Ridker, Paul M and Rivadeneira, Fernando and Rose, Lynda M and Seedorf, Udo and Siscovick, David S and Schunkert, Heribert and Selhub, Jacob and Ueland, Per M and Vollenweider, Peter and Waeber, G{\'e}rard and Waterworth, Dawn M and Watkins, Hugh and Witteman, Jacqueline C M and den Heijer, Martin and Jacques, Paul and Uitterlinden, Andr{\'e} G and Kooner, Jaspal S and Rader, Dan J and Reilly, Muredach P and Mooser, Vincent and Chasman, Daniel I and Samani, Nilesh J and Ahmadi, Kourosh R} } @article {6556, title = {Effect of genetic variants associated with plasma homocysteine levels on stroke risk.}, journal = {Stroke}, volume = {45}, year = {2014}, month = {2014 Jul}, pages = {1920-4}, abstract = {

BACKGROUND AND PURPOSE: Elevated total plasma homocysteine (tHcy) levels are known to be associated with increased risk of ischemic stroke (IS). Given that both tHcy and IS are heritable traits, we investigated a potential genetic relationship between homocysteine levels and stroke risk by assessing 18 polymorphisms previously associated with tHcy levels for their association with IS and its subtypes.

METHODS: Previous meta-analysis results from an international stroke collaborative network, METASTROKE, were used to assess association of the 18 tHcy-associated single-nucleotide polymorphisms (SNPs) in 12 389 IS cases and 62 004 controls. We also investigated the associations in regions located within 50 kb from the 18 tHcy-related SNPs and the association of a genetic risk score, including the 18 SNPs.

RESULTS: One SNP located in the RASIP1 gene and a cluster of 3 SNPs located at and near SLC17A3 were significantly associated with IS (P<0.0003) after correcting for multiple testing. For stroke subtypes, the sentinel SNP located upstream of MUT was significantly associated with small-vessel disease (P=0.0022), whereas 1 SNP located in MTHFR was significantly associated with large-vessel disease (P=0.00019). A genetic risk score, including the 18 SNPs, did not show significant association with IS or its subtypes.

CONCLUSIONS: This study found several potential associations with IS and its subtypes: an association of an MUT variant with small-vessel disease, an MTHFR variant with large-vessel disease, and associations of RASIP1 and SLC17A3 variants with overall IS.

}, keywords = {Brain Ischemia, Cohort Studies, Europe, Genetic Association Studies, Genetic Loci, Genetic Predisposition to Disease, Genetic Variation, Genome, Homocysteine, Humans, Polymorphism, Single Nucleotide, Risk, Stroke}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.114.005208}, author = {Cotlarciuc, Ioana and Malik, Rainer and Holliday, Elizabeth G and Ahmadi, Kourosh R and Par{\'e}, Guillaume and Psaty, Bruce M and Fornage, Myriam and Hasan, Nazeeha and Rinne, Paul E and Ikram, M Arfan and Markus, Hugh S and Rosand, Jonathan and Mitchell, Braxton D and Kittner, Steven J and Meschia, James F and van Meurs, Joyce B J and Uitterlinden, Andr{\'e} G and Worrall, Bradford B and Dichgans, Martin and Sharma, Pankaj} }