@article {1226, title = {Independent susceptibility markers for atrial fibrillation on chromosome 4q25.}, journal = {Circulation}, volume = {122}, year = {2010}, month = {2010 Sep 07}, pages = {976-84}, abstract = {

BACKGROUND: Genetic variants on chromosome 4q25 are associated with atrial fibrillation (AF). We sought to determine whether there is more than 1 susceptibility signal at this locus.

METHODS AND RESULTS: Thirty-four haplotype-tagging single-nucleotide polymorphisms (SNPs) at the 4q25 locus were genotyped in 790 case and 1177 control subjects from Massachusetts General Hospital and tested for association with AF. We replicated SNPs associated with AF after adjustment for the most significantly associated SNP in 5066 case and 30 661 referent subjects from the German Competence Network for Atrial Fibrillation, Atherosclerosis Risk In Communities Study, Cleveland Clinic Lone AF Study, Cardiovascular Health Study, and Rotterdam Study. All subjects were of European ancestry. A multimarker risk score composed of SNPs that tagged distinct AF susceptibility signals was constructed and tested for association with AF, and all results were subjected to meta-analysis. The previously reported SNP, rs2200733, was most significantly associated with AF (minor allele odds ratio 1.80, 95\% confidence interval 1.50 to 2.15, P=1.2 x 10(-20)) in the discovery sample. Adjustment for rs2200733 genotype revealed 2 additional susceptibility signals marked by rs17570669 and rs3853445. A graded risk of AF was observed with an increasing number of AF risk alleles at SNPs that tagged these 3 susceptibility signals.

CONCLUSIONS: We identified 2 novel AF susceptibility signals on chromosome 4q25. Consideration of multiple susceptibility signals at chromosome 4q25 identifies individuals with an increased risk of AF and may localize regulatory elements at the locus with biological relevance in the pathogenesis of AF.

}, keywords = {Aged, Aged, 80 and over, Atrial Fibrillation, Chromosome Mapping, Chromosomes, Human, Pair 4, European Continental Ancestry Group, Female, Genetic Markers, Genetic Predisposition to Disease, Haplotypes, Humans, Male, Middle Aged, Polymorphism, Single Nucleotide, Risk Factors}, issn = {1524-4539}, doi = {10.1161/CIRCULATIONAHA.109.886440}, author = {Lubitz, Steven A and Sinner, Moritz F and Lunetta, Kathryn L and Makino, Seiko and Pfeufer, Arne and Rahman, Rosanna and Veltman, Caroline E and Barnard, John and Bis, Joshua C and Danik, Stephan P and Sonni, Akshata and Shea, Marisa A and Del Monte, Federica and Perz, Siegfried and M{\"u}ller, Martina and Peters, Annette and Greenberg, Steven M and Furie, Karen L and van Noord, Charlotte and Boerwinkle, Eric and Stricker, Bruno H C and Witteman, Jacqueline and Smith, Jonathan D and Chung, Mina K and Heckbert, Susan R and Benjamin, Emelia J and Rosand, Jonathan and Arking, Dan E and Alonso, Alvaro and K{\"a}{\"a}b, Stefan and Ellinor, Patrick T} } @article {6820, title = {Novel genetic markers associate with atrial fibrillation risk in Europeans and Japanese.}, journal = {J Am Coll Cardiol}, volume = {63}, year = {2014}, month = {2014 Apr 1}, pages = {1200-10}, abstract = {

OBJECTIVES: This study sought to identify nonredundant atrial fibrillation (AF) genetic susceptibility signals and examine their cumulative relations with AF risk.

BACKGROUND: AF-associated loci span broad genomic regions that may contain multiple susceptibility signals. Whether multiple signals exist at AF loci has not been systematically explored.

METHODS: We performed association testing conditioned on the most significant, independently associated genetic markers at 9 established AF loci using 2 complementary techniques in 64,683 individuals of European ancestry (3,869 incident and 3,302 prevalent AF cases). Genetic risk scores were created and tested for association with AF in Europeans and an independent sample of 11,309 individuals of Japanese ancestry (7,916 prevalent AF cases).

RESULTS: We observed at least 4 distinct AF susceptibility signals on chromosome 4q25 upstream of PITX2, but not at the remaining 8 AF loci. A multilocus score comprised 12 genetic markers demonstrated an estimated 5-fold gradient in AF risk. We observed a similar spectrum of risk associated with these markers in Japanese. Regions containing AF signals on chromosome 4q25 displayed a greater degree of evolutionary conservation than the remainder of the locus, suggesting that they may tag regulatory elements.

CONCLUSIONS: The chromosome 4q25 AF locus is architecturally complex and harbors at least 4 AF susceptibility signals in individuals of European ancestry. Similar polygenic AF susceptibility exists between Europeans and Japanese. Future work is necessary to identify causal variants, determine mechanisms by which associated loci predispose to AF, and explore whether AF susceptibility signals classify individuals at risk for AF and related morbidity.

}, keywords = {Adult, Aged, Aged, 80 and over, Asian Continental Ancestry Group, Atrial Fibrillation, Chromosome Mapping, Chromosomes, Human, Pair 4, Europe, European Continental Ancestry Group, Female, Genetic Markers, Genetic Predisposition to Disease, Homeodomain Proteins, Humans, Japan, Male, Middle Aged, Polymorphism, Single Nucleotide, Transcription Factors}, issn = {1558-3597}, doi = {10.1016/j.jacc.2013.12.015}, author = {Lubitz, Steven A and Lunetta, Kathryn L and Lin, Honghuang and Arking, Dan E and Trompet, Stella and Li, Guo and Krijthe, Bouwe P and Chasman, Daniel I and Barnard, John and Kleber, Marcus E and D{\"o}rr, Marcus and Ozaki, Kouichi and Smith, Albert V and M{\"u}ller-Nurasyid, Martina and Walter, Stefan and Agarwal, Sunil K and Bis, Joshua C and Brody, Jennifer A and Chen, Lin Y and Everett, Brendan M and Ford, Ian and Franco, Oscar H and Harris, Tamara B and Hofman, Albert and K{\"a}{\"a}b, Stefan and Mahida, Saagar and Kathiresan, Sekar and Kubo, Michiaki and Launer, Lenore J and Macfarlane, Peter W and Magnani, Jared W and McKnight, Barbara and McManus, David D and Peters, Annette and Psaty, Bruce M and Rose, Lynda M and Rotter, Jerome I and Silbernagel, Guenther and Smith, Jonathan D and Sotoodehnia, Nona and Stott, David J and Taylor, Kent D and Tomaschitz, Andreas and Tsunoda, Tatsuhiko and Uitterlinden, Andr{\'e} G and Van Wagoner, David R and V{\"o}lker, Uwe and V{\"o}lzke, Henry and Murabito, Joanne M and Sinner, Moritz F and Gudnason, Vilmundur and Felix, Stephan B and M{\"a}rz, Winfried and Chung, Mina and Albert, Christine M and Stricker, Bruno H and Tanaka, Toshihiro and Heckbert, Susan R and Jukema, J Wouter and Alonso, Alvaro and Benjamin, Emelia J and Ellinor, Patrick T} }