Sudden cardiac arrest (SCA) is a major public health concern, particularly among African Americans where risk of cardiac arrest is higher than that of the general population, and survival is poor. While environmental factors clearly contribute to SCA risk, familial aggregation studies and advances in the molecular genetics of inherited arrhythmias suggest that genetic factors confer susceptibility to SCA in the general population. Identifying these genetic factors will provide insight into the mechanisms of SCA and potentially help target the development of novel drug therapies. Few studies to date have examined genetic risk factors among those of African descent. We propose to systematically investigate the genetic basis of SCA risk among those of African descent, focusing on both rare and common genetic variation in candidate loci selected from biologically important molecular pathways involved in rhythmogenesis, using a targeted sequencing approach. Specifically, we will sequence approximately 100 loci among 1500 African American cases and matched controls, selected from the following sets of candidate genes: genes associated with (1) SCA among those of European descent;(2) intermediate determinants of SCA, such as cardiac conduction and repolarization as measured by the surface EKG (QRS and QT intervals);and (3) Mendelian arrhythmic syndromes that lead to SCA. Beyond establishing statistical associations, we will functionally dissect the role of the genes and variants associated with SCA. We will determine the spatial and temporal distribution of the identified transcripts across a range of developmental and post-natal stages in mice through both whole mount RNA in situ analyses and sectioning of embryonic and postnatal heart. We will use zebrafish to test the hypothesis that titration of selected gene candidates during development will compromise the genesis or function of cardiovascular components. For the identified coding variation, we will compare the capacities of human RNAs containing identified coding variation with their non-variant counterparts to rescue MO-induced effects, and will similarly assay the effects of over-expression. This application represents a multi-center collaborative effort to efficiently link advances in genomics, statistical genetics, and bioinformatics, with new and existing biologic and clinical material to identify genetic determinants of SCD among African Americans. Importantly, we will use model organisms to translate genetic associations into functional studies, to elucidate the roles played by these genes in cardiac electrophysiology and arrhythmias.

Public Health Relevance

By leveraging the populations we have assembled over the past 20 years for sudden death research with advances in molecular cardiology, sequencing technology, model organism investigations, and our collaborative group's diverse expertise, this application is well positioned to identify common and rare variants and loci associated with risk of sudden cardiac arrest (SCA) among African Americans, an understudied population that is disproportionately affected by SCA. We will then follow these findings in animal models to better understand the role that these genes and variants play in SCA pathophysiology. The identification of genetic susceptibility factors will provide insight into the mechanisms of an important and devastating disease, and perhaps identify better targets for drug development and prevention.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Project (R01)
Project #
Application #
Study Section
Clinical and Integrative Cardiovascular Sciences Study Section (CICS)
Program Officer
Wang, Lan-Hsiang
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Washington
Internal Medicine/Medicine
Schools of Medicine
United States
Zip Code
Konety, Suma H; Koene, Ryan J; Norby, Faye L et al. (2016) Echocardiographic Predictors of Sudden Cardiac Death: The Atherosclerosis Risk in Communities Study and Cardiovascular Health Study. Circ Cardiovasc Imaging 9:
Waks, Jonathan W; Sitlani, Colleen M; Soliman, Elsayed Z et al. (2016) Global Electric Heterogeneity Risk Score for Prediction of Sudden Cardiac Death in the General Population: The Atherosclerosis Risk in Communities (ARIC) and Cardiovascular Health (CHS) Studies. Circulation 133:2222-34
Suzuki, Takeki; Agarwal, Sunil K; Deo, Rajat et al. (2016) Kidney function and sudden cardiac death in the community: The Atherosclerosis Risk in Communities (ARIC) Study. Am Heart J 180:46-53
Ma, Yiyi; Follis, Jack L; Smith, Caren E et al. (2016) Interaction of methylation-related genetic variants with circulating fatty acids on plasma lipids: a meta-analysis of 7 studies and methylation analysis of 3 studies in the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium. Am J Clin Nutr 103:567-78
Deo, Rajat; Norby, Faye L; Katz, Ronit et al. (2016) Development and Validation of a Sudden Cardiac Death Prediction Model for the General Population. Circulation 134:806-16
Ligthart, Symen; Marzi, Carola; Aslibekyan, Stella et al. (2016) DNA methylation signatures of chronic low-grade inflammation are associated with complex diseases. Genome Biol 17:255
Wander, P L; Enquobahrie, D A; Pritchard, C C et al. (2016) Circulating microRNAs and sudden cardiac arrest outcomes. Resuscitation 106:96-101
Magnani, Jared W; Brody, Jennifer A; Prins, Bram P et al. (2014) Sequencing of SCN5A identifies rare and common variants associated with cardiac conduction: Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. Circ Cardiovasc Genet 7:365-73
Ilkhanoff, Leonard; Arking, Dan E; Lemaitre, Rozenn N et al. (2014) A common SCN5A variant is associated with PR interval and atrial fibrillation among African Americans. J Cardiovasc Electrophysiol 25:1150-7
Smith, J Gustav; Avery, Christy L; Evans, Daniel S et al. (2012) Impact of ancestry and common genetic variants on QT interval in African Americans. Circ Cardiovasc Genet 5:647-55