@article {6600, title = {Integrating genetic, transcriptional, and functional analyses to identify 5 novel genes for atrial fibrillation.}, journal = {Circulation}, volume = {130}, year = {2014}, month = {2014 Oct 7}, pages = {1225-35}, abstract = {

BACKGROUND: Atrial fibrillation (AF) affects >30 million individuals worldwide and is associated with an increased risk of stroke, heart failure, and death. AF is highly heritable, yet the genetic basis for the arrhythmia remains incompletely understood.

METHODS AND RESULTS: To identify new AF-related genes, we used a multifaceted approach, combining large-scale genotyping in 2 ethnically distinct populations, cis-eQTL (expression quantitative trait loci) mapping, and functional validation. Four novel loci were identified in individuals of European descent near the genes NEURL (rs12415501; relative risk [RR]=1.18; 95\% confidence interval [CI], 1.13-1.23; P=6.5{\texttimes}10(-16)), GJA1 (rs13216675; RR=1.10; 95\% CI, 1.06-1.14; P=2.2{\texttimes}10(-8)), TBX5 (rs10507248; RR=1.12; 95\% CI, 1.08-1.16; P=5.7{\texttimes}10(-11)), and CAND2 (rs4642101; RR=1.10; 95\% CI, 1.06-1.14; P=9.8{\texttimes}10(-9)). In Japanese, novel loci were identified near NEURL (rs6584555; RR=1.32; 95\% CI, 1.26-1.39; P=2.0{\texttimes}10(-25)) and CUX2 (rs6490029; RR=1.12; 95\% CI, 1.08-1.16; P=3.9{\texttimes}10(-9)). The top single-nucleotide polymorphisms or their proxies were identified as cis-eQTLs for the genes CAND2 (P=2.6{\texttimes}10(-19)), GJA1 (P=2.66{\texttimes}10(-6)), and TBX5 (P=1.36{\texttimes}10(-5)). Knockdown of the zebrafish orthologs of NEURL and CAND2 resulted in prolongation of the atrial action potential duration (17\% and 45\%, respectively).

CONCLUSIONS: We have identified 5 novel loci for AF. Our results expand the diversity of genetic pathways implicated in AF and provide novel molecular targets for future biological and pharmacological investigation.

}, keywords = {Aged, Animals, Atrial Fibrillation, Chromosome Mapping, Connexin 43, Europe, Female, Gene Knockdown Techniques, Genetic Loci, Genetic Predisposition to Disease, Genotype, Homeodomain Proteins, Humans, Japan, Male, Middle Aged, Muscle Proteins, Nuclear Proteins, Quantitative Trait Loci, Repressor Proteins, T-Box Domain Proteins, Transcription Factors, Ubiquitin-Protein Ligases, Zebrafish, Zebrafish Proteins}, issn = {1524-4539}, doi = {10.1161/CIRCULATIONAHA.114.009892}, author = {Sinner, Moritz F and Tucker, Nathan R and Lunetta, Kathryn L and Ozaki, Kouichi and Smith, J Gustav and Trompet, Stella and Bis, Joshua C and Lin, Honghuang and Chung, Mina K and Nielsen, Jonas B and Lubitz, Steven A and Krijthe, Bouwe P and Magnani, Jared W and Ye, Jiangchuan and Gollob, Michael H and Tsunoda, Tatsuhiko and M{\"u}ller-Nurasyid, Martina and Lichtner, Peter and Peters, Annette and Dolmatova, Elena and Kubo, Michiaki and Smith, Jonathan D and Psaty, Bruce M and Smith, Nicholas L and Jukema, J Wouter and Chasman, Daniel I and Albert, Christine M and Ebana, Yusuke and Furukawa, Tetsushi and Macfarlane, Peter W and Harris, Tamara B and Darbar, Dawood and D{\"o}rr, Marcus and Holst, Anders G and Svendsen, Jesper H and Hofman, Albert and Uitterlinden, Andr{\'e} G and Gudnason, Vilmundur and Isobe, Mitsuaki and Malik, Rainer and Dichgans, Martin and Rosand, Jonathan and Van Wagoner, David R and Benjamin, Emelia J and Milan, David J and Melander, Olle and Heckbert, Susan R and Ford, Ian and Liu, Yongmei and Barnard, John and Olesen, Morten S and Stricker, Bruno H C and Tanaka, Toshihiro 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} }