PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (118)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
more »
1.  Genetic fine-mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci 
Gaulton, Kyle J | Ferreira, Teresa | Lee, Yeji | Raimondo, Anne | Mägi, Reedik | Reschen, Michael E | Mahajan, Anubha | Locke, Adam | Rayner, N William | Robertson, Neil | Scott, Robert A | Prokopenko, Inga | Scott, Laura J | Green, Todd | Sparso, Thomas | Thuillier, Dorothee | Yengo, Loic | Grallert, Harald | Wahl, Simone | Frånberg, Mattias | Strawbridge, Rona J | Kestler, Hans | Chheda, Himanshu | Eisele, Lewin | Gustafsson, Stefan | Steinthorsdottir, Valgerdur | Thorleifsson, Gudmar | Qi, Lu | Karssen, Lennart C | van Leeuwen, Elisabeth M | Willems, Sara M | Li, Man | Chen, Han | Fuchsberger, Christian | Kwan, Phoenix | Ma, Clement | Linderman, Michael | Lu, Yingchang | Thomsen, Soren K | Rundle, Jana K | Beer, Nicola L | van de Bunt, Martijn | Chalisey, Anil | Kang, Hyun Min | Voight, Benjamin F | Abecasis, Goncalo R | Almgren, Peter | Baldassarre, Damiano | Balkau, Beverley | Benediktsson, Rafn | Blüher, Matthias | Boeing, Heiner | Bonnycastle, Lori L | Borringer, Erwin P | Burtt, Noël P | Carey, Jason | Charpentier, Guillaume | Chines, Peter S | Cornelis, Marilyn C | Couper, David J | Crenshaw, Andrew T | van Dam, Rob M | Doney, Alex SF | Dorkhan, Mozhgan | Edkins, Sarah | Eriksson, Johan G | Esko, Tonu | Eury, Elodie | Fadista, João | Flannick, Jason | Fontanillas, Pierre | Fox, Caroline | Franks, Paul W | Gertow, Karl | Gieger, Christian | Gigante, Bruna | Gottesman, Omri | Grant, George B | Grarup, Niels | Groves, Christopher J | Hassinen, Maija | Have, Christian T | Herder, Christian | Holmen, Oddgeir L | Hreidarsson, Astradur B | Humphries, Steve E | Hunter, David J | Jackson, Anne U | Jonsson, Anna | Jørgensen, Marit E | Jørgensen, Torben | Kao, Wen-Hong L | Kerrison, Nicola D | Kinnunen, Leena | Klopp, Norman | Kong, Augustine | Kovacs, Peter | Kraft, Peter | Kravic, Jasmina | Langford, Cordelia | Leander, Karin | Liang, Liming | Lichtner, Peter | Lindgren, Cecilia M | Lindholm, Eero | Linneberg, Allan | Liu, Ching-Ti | Lobbens, Stéphane | Luan, Jian’an | Lyssenko, Valeriya | Mӓnnistö, Satu | McLeod, Olga | Meyer, Julia | Mihailov, Evelin | Mirza, Ghazala | Mühleisen, Thomas W | Müller-Nurasyid, Martina | Navarro, Carmen | Nöthen, Markus M | Oskolkov, Nikolay N | Owen, Katharine R | Palli, Domenico | Pechlivanis, Sonali | Peltonen, Leena | Perry, John RB | Platou, Carl GP | Roden, Michael | Ruderfer, Douglas | Rybin, Denis | van der Schouw, Yvonne T | Sennblad, Bengt | Sigurđsson, Gunnar | Stančáková, Alena | Steinbach, Gerald | Storm, Petter | Strauch, Konstantin | Stringham, Heather M | Sun, Qi | Thorand, Barbara | Tikkanen, Emmi | Tonjes, Anke | Trakalo, Joseph | Tremoli, Elena | Tuomi, Tiinamaija | Wennauer, Roman | Wiltshire, Steven | Wood, Andrew R | Zeggini, Eleftheria | Dunham, Ian | Birney, Ewan | Pasquali, Lorenzo | Ferrer, Jorge | Loos, Ruth JF | Dupuis, Josée | Florez, Jose C | Boerwinkle, Eric | Pankow, James S | van Duijn, Cornelia | Sijbrands, Eric | Meigs, James B | Hu, Frank B | Thorsteinsdottir, Unnur | Stefansson, Kari | Lakka, Timo A | Rauramaa, Rainer | Stumvoll, Michael | Pedersen, Nancy L | Lind, Lars | Keinanen-Kiukaanniemi, Sirkka M | Korpi-Hyövӓlti, Eeva | Saaristo, Timo E | Saltevo, Juha | Kuusisto, Johanna | Laakso, Markku | Metspalu, Andres | Erbel, Raimund | Jöckel, Karl-Heinz | Moebus, Susanne | Ripatti, Samuli | Salomaa, Veikko | Ingelsson, Erik | Boehm, Bernhard O | Bergman, Richard N | Collins, Francis S | Mohlke, Karen L | Koistinen, Heikki | Tuomilehto, Jaakko | Hveem, Kristian | Njølstad, Inger | Deloukas, Panagiotis | Donnelly, Peter J | Frayling, Timothy M | Hattersley, Andrew T | de Faire, Ulf | Hamsten, Anders | Illig, Thomas | Peters, Annette | Cauchi, Stephane | Sladek, Rob | Froguel, Philippe | Hansen, Torben | Pedersen, Oluf | Morris, Andrew D | Palmer, Collin NA | Kathiresan, Sekar | Melander, Olle | Nilsson, Peter M | Groop, Leif C | Barroso, Inês | Langenberg, Claudia | Wareham, Nicholas J | O’Callaghan, Christopher A | Gloyn, Anna L | Altshuler, David | Boehnke, Michael | Teslovich, Tanya M | McCarthy, Mark I | Morris, Andrew P
Nature genetics  2015;47(12):1415-1425.
We performed fine-mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in/near KCNQ1. “Credible sets” of variants most likely to drive each distinct signal mapped predominantly to non-coding sequence, implying that T2D association is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine-mapping implicated rs10830963 as driving T2D association. We confirmed that this T2D-risk allele increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D-risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.
doi:10.1038/ng.3437
PMCID: PMC4666734  PMID: 26551672
2.  Genetic fine-mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci 
Gaulton, Kyle J | Ferreira, Teresa | Lee, Yeji | Raimondo, Anne | Mägi, Reedik | Reschen, Michael E | Mahajan, Anubha | Locke, Adam | Rayner, N William | Robertson, Neil | Scott, Robert A | Prokopenko, Inga | Scott, Laura J | Green, Todd | Sparso, Thomas | Thuillier, Dorothee | Yengo, Loic | Grallert, Harald | Wahl, Simone | Frånberg, Mattias | Strawbridge, Rona J | Kestler, Hans | Chheda, Himanshu | Eisele, Lewin | Gustafsson, Stefan | Steinthorsdottir, Valgerdur | Thorleifsson, Gudmar | Qi, Lu | Karssen, Lennart C | van Leeuwen, Elisabeth M | Willems, Sara M | Li, Man | Chen, Han | Fuchsberger, Christian | Kwan, Phoenix | Ma, Clement | Linderman, Michael | Lu, Yingchang | Thomsen, Soren K | Rundle, Jana K | Beer, Nicola L | van de Bunt, Martijn | Chalisey, Anil | Kang, Hyun Min | Voight, Benjamin F | Abecasis, Goncalo R | Almgren, Peter | Baldassarre, Damiano | Balkau, Beverley | Benediktsson, Rafn | Blüher, Matthias | Boeing, Heiner | Bonnycastle, Lori L | Borringer, Erwin P | Burtt, Noël P | Carey, Jason | Charpentier, Guillaume | Chines, Peter S | Cornelis, Marilyn C | Couper, David J | Crenshaw, Andrew T | van Dam, Rob M | Doney, Alex SF | Dorkhan, Mozhgan | Edkins, Sarah | Eriksson, Johan G | Esko, Tonu | Eury, Elodie | Fadista, João | Flannick, Jason | Fontanillas, Pierre | Fox, Caroline | Franks, Paul W | Gertow, Karl | Gieger, Christian | Gigante, Bruna | Gottesman, Omri | Grant, George B | Grarup, Niels | Groves, Christopher J | Hassinen, Maija | Have, Christian T | Herder, Christian | Holmen, Oddgeir L | Hreidarsson, Astradur B | Humphries, Steve E | Hunter, David J | Jackson, Anne U | Jonsson, Anna | Jørgensen, Marit E | Jørgensen, Torben | Kao, Wen-Hong L | Kerrison, Nicola D | Kinnunen, Leena | Klopp, Norman | Kong, Augustine | Kovacs, Peter | Kraft, Peter | Kravic, Jasmina | Langford, Cordelia | Leander, Karin | Liang, Liming | Lichtner, Peter | Lindgren, Cecilia M | Lindholm, Eero | Linneberg, Allan | Liu, Ching-Ti | Lobbens, Stéphane | Luan, Jian’an | Lyssenko, Valeriya | Männistö, Satu | McLeod, Olga | Meyer, Julia | Mihailov, Evelin | Mirza, Ghazala | Mühleisen, Thomas W | Müller-Nurasyid, Martina | Navarro, Carmen | Nöthen, Markus M | Oskolkov, Nikolay N | Owen, Katharine R | Palli, Domenico | Pechlivanis, Sonali | Peltonen, Leena | Perry, John RB | Platou, Carl GP | Roden, Michael | Ruderfer, Douglas | Rybin, Denis | van der Schouw, Yvonne T | Sennblad, Bengt | Sigurðsson, Gunnar | Stančáková, Alena | Steinbach, Gerald | Storm, Petter | Strauch, Konstantin | Stringham, Heather M | Sun, Qi | Thorand, Barbara | Tikkanen, Emmi | Tonjes, Anke | Trakalo, Joseph | Tremoli, Elena | Tuomi, Tiinamaija | Wennauer, Roman | Wiltshire, Steven | Wood, Andrew R | Zeggini, Eleftheria | Dunham, Ian | Birney, Ewan | Pasquali, Lorenzo | Ferrer, Jorge | Loos, Ruth JF | Dupuis, Josée | Florez, Jose C | Boerwinkle, Eric | Pankow, James S | van Duijn, Cornelia | Sijbrands, Eric | Meigs, James B | Hu, Frank B | Thorsteinsdottir, Unnur | Stefansson, Kari | Lakka, Timo A | Rauramaa, Rainer | Stumvoll, Michael | Pedersen, Nancy L | Lind, Lars | Keinanen-Kiukaanniemi, Sirkka M | Korpi-Hyövälti, Eeva | Saaristo, Timo E | Saltevo, Juha | Kuusisto, Johanna | Laakso, Markku | Metspalu, Andres | Erbel, Raimund | Jöckel, Karl-Heinz | Moebus, Susanne | Ripatti, Samuli | Salomaa, Veikko | Ingelsson, Erik | Boehm, Bernhard O | Bergman, Richard N | Collins, Francis S | Mohlke, Karen L | Koistinen, Heikki | Tuomilehto, Jaakko | Hveem, Kristian | Njølstad, Inger | Deloukas, Panagiotis | Donnelly, Peter J | Frayling, Timothy M | Hattersley, Andrew T | de Faire, Ulf | Hamsten, Anders | Illig, Thomas | Peters, Annette | Cauchi, Stephane | Sladek, Rob | Froguel, Philippe | Hansen, Torben | Pedersen, Oluf | Morris, Andrew D | Palmer, Collin NA | Kathiresan, Sekar | Melander, Olle | Nilsson, Peter M | Groop, Leif C | Barroso, Inês | Langenberg, Claudia | Wareham, Nicholas J | O’Callaghan, Christopher A | Gloyn, Anna L | Altshuler, David | Boehnke, Michael | Teslovich, Tanya M | McCarthy, Mark I | Morris, Andrew P
Nature genetics  2015;47(12):1415-1425.
We performed fine-mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in/near KCNQ1. “Credible sets” of variants most likely to drive each distinct signal mapped predominantly to non-coding sequence, implying that T2D association is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine-mapping implicated rs10830963 as driving T2D association. We confirmed that this T2D-risk allele increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D-risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.
doi:10.1038/ng.3437
PMCID: PMC4666734  PMID: 26551672
3.  IGF2BP2/IMP2 Deficient Mice Resist Obesity through enhanced translation of Ucp1 mRNA and other mRNAs encoding Mitochondrial Proteins 
Cell metabolism  2015;21(4):609-621.
Although variants in the IGF2BP2/IMP2 gene confer risk for Type 2 diabetes, IMP2, an RNA binding protein, is not known to regulate metabolism. Imp2−/− mice gain less lean mass after weaning and have increased lifespan. Imp2−/− mice are highly resistant to diet-induced obesity and fatty liver and display superior glucose tolerance and insulin sensitivity, increased energy expenditure and better defense of core temperature on cold exposure. Imp2−/− brown fat and Imp2−/− brown adipocytes differentiated in vitro contain more UCP1 polypeptide than Imp2+/+ despite similar levels of Ucp1 mRNA; the Imp2−/− adipocytes also exhibit greater uncoupled oxygen consumption. IMP2 binds the mRNAs encoding Ucp1 and other mitochondrial components, and most exhibit increased translational efficiency in the absence of IMP2. In vitro IMP2 inhibits translation of mRNAs bearing the Ucp1 untranslated segments. Thus IMP2 limits longevity and regulates nutrient and energy metabolism in the mouse by controlling the translation of its client mRNAs.
Graphical Abstract
doi:10.1016/j.cmet.2015.03.006
PMCID: PMC4663978  PMID: 25863250
4.  Pathways Targeted by Antidiabetes Drugs Are Enriched for Multiple Genes Associated With Type 2 Diabetes Risk 
Diabetes  2014;64(4):1470-1483.
Genome-wide association studies (GWAS) have uncovered >65 common variants associated with type 2 diabetes (T2D); however, their relevance for drug development is not yet clear. Of note, the first two T2D-associated loci (PPARG and KCNJ11/ABCC8) encode known targets of antidiabetes medications. We therefore tested whether other genes/pathways targeted by antidiabetes drugs are associated with T2D. We compiled a list of 102 genes in pathways targeted by marketed antidiabetic medications and applied Gene Set Enrichment Analysis (MAGENTA [Meta-Analysis Gene-set Enrichment of variaNT Associations]) to this gene set, using available GWAS meta-analyses for T2D and seven quantitative glycemic traits. We detected a strong enrichment of drug target genes associated with T2D (P = 2 × 10−5; 14 potential new associations), primarily driven by insulin and thiazolidinedione (TZD) targets, which was replicated in an independent meta-analysis (Metabochip). The glycemic traits yielded no enrichment. The T2D enrichment signal was largely due to multiple genes of modest effects (P = 4 × 10−4, after removing known loci), highlighting new associations for follow-up (ACSL1, NFKB1, SLC2A2, incretin targets). Furthermore, we found that TZD targets were enriched for LDL cholesterol associations, illustrating the utility of this approach in identifying potential side effects. These results highlight the potential biomedical relevance of genes revealed by GWAS and may provide new avenues for tailored therapy and T2D treatment design.
doi:10.2337/db14-0703
PMCID: PMC4375079  PMID: 25368101
5.  Transancestral fine-mapping of four type 2 diabetes susceptibility loci highlights potential causal regulatory mechanisms 
Human Molecular Genetics  2016;25(10):2070-2081.
To gain insight into potential regulatory mechanisms through which the effects of variants at four established type 2 diabetes (T2D) susceptibility loci (CDKAL1, CDKN2A-B, IGF2BP2 and KCNQ1) are mediated, we undertook transancestral fine-mapping in 22 086 cases and 42 539 controls of East Asian, European, South Asian, African American and Mexican American descent. Through high-density imputation and conditional analyses, we identified seven distinct association signals at these four loci, each with allelic effects on T2D susceptibility that were homogenous across ancestry groups. By leveraging differences in the structure of linkage disequilibrium between diverse populations, and increased sample size, we localised the variants most likely to drive each distinct association signal. We demonstrated that integration of these genetic fine-mapping data with genomic annotation can highlight potential causal regulatory elements in T2D-relevant tissues. These analyses provide insight into the mechanisms through which T2D association signals are mediated, and suggest future routes to understanding the biology of specific disease susceptibility loci.
doi:10.1093/hmg/ddw048
PMCID: PMC5062576  PMID: 26911676
6.  Structural forms of the human amylase locus and their relationships to SNPs, haplotypes, and obesity 
Nature genetics  2015;47(8):921-925.
Hundreds of genes reside in structurally complex, poorly understood regions of the human genome1-3. One such region contains the three amylase genes (AMY2B, AMY2A, and AMY1) responsible for digesting starch into sugar. The copy number of AMY1 is reported to be the genome’s largest influence on obesity4, though genome-wide association studies for obesity have found this locus unremarkable. Using whole genome sequence analysis3,5, droplet digital PCR6, and genome mapping7, we identified eight common structural haplotypes of the amylase locus that suggest its mutational history. We found that AMY1 copy number in individuals’ genomes is generally even (rather than odd) and partially correlates to nearby SNPs, which do not associate with BMI. We measured amylase gene copy number in 1,000 obese or lean Estonians and in two other cohorts totaling ~3,500 individuals. We had 99% power to detect the lower bound of the reported effects on BMI4, yet found no association.
doi:10.1038/ng.3340
PMCID: PMC4712930  PMID: 26098870
7.  A null mutation in ANGPTL8 does not associate with either plasma glucose or type 2 diabetes in humans 
Background
Experiments in mice initially suggested a role for the protein angiopoietin-like 8 (ANGPTL8) in glucose homeostasis. However, subsequent experiments in model systems have challenged this proposed role. We sought to better understand the importance of ANGPTL8 in human glucose homeostasis by examining the association of a null mutation in ANGPTL8 with fasting glucose levels and risk for type 2 diabetes.
Methods
A naturally-occurring null mutation in human ANGPTL8 (rs145464906; c.361C > T; p.Q121X) is carried by ~1 in 1000 individuals of European ancestry and is associated with higher levels of plasma high-density lipoprotein cholesterol, suggesting that this mutation has functional significance. We examined the association of p.Q121X with fasting glucose levels and risk for type 2 diabetes in up to 95,558 individuals (14,824 type 2 diabetics and 80,734 controls).
Results
We found no significant association of p.Q121X with either fasting glucose or type 2 diabetes (p-value = 0.90 and 0.65, respectively). Given our sample sizes, we had >98 % power to detect at least a 0.23 mmol/L effect on plasma glucose and >95 % power to detect a 70 % increase in risk for type 2 diabetes.
Conclusion
Disruption of ANGPTL8 function in humans does not seem to have a large effect on measures of glucose tolerance.
Electronic supplementary material
The online version of this article (doi:10.1186/s12902-016-0088-8) contains supplementary material, which is available to authorized users.
doi:10.1186/s12902-016-0088-8
PMCID: PMC4730725  PMID: 26822414
Betatrophin; Angiopoietin-like 8; rs145464906
8.  Whole-exome imputation of sequence variants identified two novel alleles associated with adult body height in African Americans 
Human Molecular Genetics  2014;23(24):6607-6615.
Adult body height is a quantitative trait for which genome-wide association studies (GWAS) have identified numerous loci, primarily in European populations. These loci, comprising common variants, explain <10% of the phenotypic variance in height. We searched for novel associations between height and common (minor allele frequency, MAF ≥5%) or infrequent (0.5% < MAF < 5%) variants across the exome in African Americans. Using a reference panel of 1692 African Americans and 471 Europeans from the National Heart, Lung, and Blood Institute's (NHLBI) Exome Sequencing Project (ESP), we imputed whole-exome sequence data into 13 719 African Americans with existing array-based GWAS data (discovery). Variants achieving a height-association threshold of P < 5E−06 in the imputed dataset were followed up in an independent sample of 1989 African Americans with whole-exome sequence data (replication). We used P < 2.5E−07 (=0.05/196 779 variants) to define statistically significant associations in meta-analyses combining the discovery and replication sets (N = 15 708). We discovered and replicated three independent loci for association: 5p13.3/C5orf22/rs17410035 (MAF = 0.10, β = 0.64 cm, P = 8.3E−08), 13q14.2/SPRYD7/rs114089985 (MAF = 0.03, β = 1.46 cm, P = 4.8E−10) and 17q23.3/GH2/rs2006123 (MAF = 0.30; β = 0.47 cm; P = 4.7E−09). Conditional analyses suggested 5p13.3 (C5orf22/rs17410035) and 13q14.2 (SPRYD7/rs114089985) may harbor novel height alleles independent of previous GWAS-identified variants (r2 with GWAS loci <0.01); whereas 17q23.3/GH2/rs2006123 was correlated with GWAS-identified variants in European and African populations. Notably, 13q14.2/rs114089985 is infrequent in African Americans (MAF = 3%), extremely rare in European Americans (MAF = 0.03%), and monomorphic in Asian populations, suggesting it may be an African-American-specific height allele. Our findings demonstrate that whole-exome imputation of sequence variants can identify low-frequency variants and discover novel variants in non-European populations.
doi:10.1093/hmg/ddu361
PMCID: PMC4240196  PMID: 25027330
9.  Integrated allelic, transcriptional, and phenomic dissection of the cardiac effects of titin truncations in health and disease 
Science translational medicine  2015;7(270):270ra6.
The recent discovery of heterozygous human mutations that truncate full-length titin (TTN, an abundant structural, sensory, and signaling filament in muscle) as a common cause of end-stage dilated cardiomyopathy (DCM) provides new prospects for improving heart failure management. However, realization of this opportunity has been hindered by the burden of TTN truncating variants (TTNtv) in the general population and uncertainty about their consequences in health or disease. To elucidate the effects of TTNtv, we coupled TTN gene sequencing with cardiac phenotyping in 5,267 individuals across the spectrum of cardiac physiology, and integrated these data with RNA and protein analyses of human heart tissues. We report diversity of TTN isoform expression in the heart, define the relative inclusion of TTN exons in different isoforms, and demonstrate that these data, coupled with TTNtv position, provide a robust strategy to discriminate pathogenic from benign TTNtv. We show that TTNtv is the most common genetic cause for DCM in ambulant patients in the community, identify clinically important manifestations of TTNtv-positive DCM, and define the penetrance and outcomes of TTNtv in the general population. By integrating genetic, transcriptome, and protein analyses we provide evidence for a length-dependent, dominant negative mechanism of disease. These data inform diagnostic criteria and management strategies for TTNtv-positive DCM patients and for TTNtv that are identified as incidental findings.
doi:10.1126/scitranslmed.3010134
PMCID: PMC4560092  PMID: 25589632
10.  Multiple rare alleles at LDLR and APOA5 confer risk for early-onset myocardial infarction 
Do, Ron | Stitziel, Nathan O. | Won, Hong-Hee | Jørgensen, Anders Berg | Duga, Stefano | Merlini, Pier Angelica | Kiezun, Adam | Farrall, Martin | Goel, Anuj | Zuk, Or | Guella, Illaria | Asselta, Rosanna | Lange, Leslie A. | Peloso, Gina M. | Auer, Paul L. | Girelli, Domenico | Martinelli, Nicola | Farlow, Deborah N. | DePristo, Mark A. | Roberts, Robert | Stewart, Alexander F.R. | Saleheen, Danish | Danesh, John | Epstein, Stephen E. | Sivapalaratnam, Suthesh | Hovingh, G. Kees | Kastelein, John J. | Samani, Nilesh J. | Schunkert, Heribert | Erdmann, Jeanette | Shah, Svati H. | Kraus, William E. | Davies, Robert | Nikpay, Majid | Johansen, Christopher T. | Wang, Jian | Hegele, Robert A. | Hechter, Eliana | Marz, Winfried | Kleber, Marcus E. | Huang, Jie | Johnson, Andrew D. | Li, Mingyao | Burke, Greg L. | Gross, Myron | Liu, Yongmei | Assimes, Themistocles L. | Heiss, Gerardo | Lange, Ethan M. | Folsom, Aaron R. | Taylor, Herman A. | Olivieri, Oliviero | Hamsten, Anders | Clarke, Robert | Reilly, Dermot F. | Yin, Wu | Rivas, Manuel A. | Donnelly, Peter | Rossouw, Jacques E. | Psaty, Bruce M. | Herrington, David M. | Wilson, James G. | Rich, Stephen S. | Bamshad, Michael J. | Tracy, Russell P. | Cupples, L. Adrienne | Rader, Daniel J. | Reilly, Muredach P. | Spertus, John A. | Cresci, Sharon | Hartiala, Jaana | Tang, W.H. Wilson | Hazen, Stanley L. | Allayee, Hooman | Reiner, Alex P. | Carlson, Christopher S. | Kooperberg, Charles | Jackson, Rebecca D. | Boerwinkle, Eric | Lander, Eric S. | Schwartz, Stephen M. | Siscovick, David S. | McPherson, Ruth | Tybjaerg-Hansen, Anne | Abecasis, Goncalo R. | Watkins, Hugh | Nickerson, Deborah A. | Ardissino, Diego | Sunyaev, Shamil R. | O’Donnell, Christopher J. | Altshuler, David | Gabriel, Stacey | Kathiresan, Sekar
Nature  2014;518(7537):102-106.
Summary
Myocardial infarction (MI), a leading cause of death around the world, displays a complex pattern of inheritance1,2. When MI occurs early in life, the role of inheritance is substantially greater1. Previously, rare mutations in low-density lipoprotein (LDL) genes have been shown to contribute to MI risk in individual families3–8 whereas common variants at more than 45 loci have been associated with MI risk in the population9–15. Here, we evaluate the contribution of rare mutations to MI risk in the population. We sequenced the protein-coding regions of 9,793 genomes from patients with MI at an early age (≤50 years in males and ≤60 years in females) along with MI-free controls. We identified two genes where rare coding-sequence mutations were more frequent in cases versus controls at exome-wide significance. At low-density lipoprotein receptor (LDLR), carriers of rare, damaging mutations (3.1% of cases versus 1.3% of controls) were at 2.4-fold increased risk for MI; carriers of null alleles at LDLR were at even higher risk (13-fold difference). This sequence-based estimate of the proportion of early MI cases due to LDLR mutations is remarkably similar to an estimate made more than 40 years ago using total cholesterol16. At apolipoprotein A-V (APOA5), carriers of rare nonsynonymous mutations (1.4% of cases versus 0.6% of controls) were at 2.2-fold increased risk for MI. When compared with non-carriers, LDLR mutation carriers had higher plasma LDL cholesterol whereas APOA5 mutation carriers had higher plasma triglycerides. Recent evidence has connected MI risk with coding sequence mutations at two genes functionally related to APOA5, namely lipoprotein lipase15,17 and apolipoprotein C318,19. When combined, these observations suggest that, beyond LDL cholesterol, disordered metabolism of triglyceride-rich lipoproteins contributes to MI risk.
doi:10.1038/nature13917
PMCID: PMC4319990  PMID: 25487149
11.  Genome-wide meta-analysis in alopecia areata resolves HLA associations and reveals two new susceptibility loci 
Nature communications  2015;6:5966.
Alopecia areata (AA) is a prevalent autoimmune disease with ten known susceptibility loci. Here we perform the first meta-analysis in AA by combining data from two genome-wide association studies (GWAS), and replication with supplemented ImmunoChip data for a total of 3,253 cases and 7,543 controls. The strongest region of association is the MHC, where we fine-map 4 independent effects, all implicating HLA-DR as a key etiologic driver. Outside the MHC, we identify two novel loci that exceed statistical significance, containing ACOXL/BCL2L11(BIM) (2q13); GARP (LRRC32) (11q13.5), as well as a third nominally significant region SH2B3(LNK)/ATXN2 (12q24.12). Candidate susceptibility gene expression analysis in these regions demonstrates expression in relevant immune cells and the hair follicle. We integrate our results with data from seven other autoimmune diseases and provide insight into the alignment of AA within these disorders. Our findings uncover new molecular pathways disrupted in AA, including autophagy/apoptosis, TGFß/Tregs and JAK kinase signaling, and support the causal role of aberrant immune processes in AA.
doi:10.1038/ncomms6966
PMCID: PMC4451186  PMID: 25608926
13.  Age-Related Clonal Hematopoiesis Associated with Adverse Outcomes 
The New England journal of medicine  2014;371(26):2488-2498.
BACKGROUND
The incidence of hematologic cancers increases with age. These cancers are associated with recurrent somatic mutations in specific genes. We hypothesized that such mutations would be detectable in the blood of some persons who are not known to have hematologic disorders.
METHODS
We analyzed whole-exome sequencing data from DNA in the peripheral-blood cells of 17,182 persons who were unselected for hematologic phenotypes. We looked for somatic mutations by identifying previously characterized single-nucleotide variants and small insertions or deletions in 160 genes that are recurrently mutated in hematologic cancers. The presence of mutations was analyzed for an association with hematologic phenotypes, survival, and cardiovascular events.
RESULTS
Detectable somatic mutations were rare in persons younger than 40 years of age but rose appreciably in frequency with age. Among persons 70 to 79 years of age, 80 to 89 years of age, and 90 to 108 years of age, these clonal mutations were observed in 9.5% (219 of 2300 persons), 11.7% (37 of 317), and 18.4% (19 of 103), respectively. The majority of the variants occurred in three genes: DNMT3A, TET2, and ASXL1. The presence of a somatic mutation was associated with an increase in the risk of hematologic cancer (hazard ratio, 11.1; 95% confidence interval [CI], 3.9 to 32.6), an increase in all-cause mortality (hazard ratio, 1.4; 95% CI, 1.1 to 1.8), and increases in the risks of incident coronary heart disease (hazard ratio, 2.0; 95% CI, 1.2 to 3.4) and ischemic stroke (hazard ratio, 2.6; 95% CI, 1.4 to 4.8).
CONCLUSIONS
Age-related clonal hematopoiesis is a common condition that is associated with increases in the risk of hematologic cancer and in all-cause mortality, with the latter possibly due to an increased risk of cardiovascular disease. (Funded by the National Institutes of Health and others.)
doi:10.1056/NEJMoa1408617
PMCID: PMC4306669  PMID: 25426837
14.  The Power of Gene-Based Rare Variant Methods to Detect Disease-Associated Variation and Test Hypotheses About Complex Disease 
PLoS Genetics  2015;11(4):e1005165.
Genome and exome sequencing in large cohorts enables characterization of the role of rare variation in complex diseases. Success in this endeavor, however, requires investigators to test a diverse array of genetic hypotheses which differ in the number, frequency and effect sizes of underlying causal variants. In this study, we evaluated the power of gene-based association methods to interrogate such hypotheses, and examined the implications for study design. We developed a flexible simulation approach, using 1000 Genomes data, to (a) generate sequence variation at human genes in up to 10K case-control samples, and (b) quantify the statistical power of a panel of widely used gene-based association tests under a variety of allelic architectures, locus effect sizes, and significance thresholds. For loci explaining ~1% of phenotypic variance underlying a common dichotomous trait, we find that all methods have low absolute power to achieve exome-wide significance (~5-20% power at α=2.5×10-6) in 3K individuals; even in 10K samples, power is modest (~60%). The combined application of multiple methods increases sensitivity, but does so at the expense of a higher false positive rate. MiST, SKAT-O, and KBAC have the highest individual mean power across simulated datasets, but we observe wide architecture-dependent variability in the individual loci detected by each test, suggesting that inferences about disease architecture from analysis of sequencing studies can differ depending on which methods are used. Our results imply that tens of thousands of individuals, extensive functional annotation, or highly targeted hypothesis testing will be required to confidently detect or exclude rare variant signals at complex disease loci.
Author Summary
Re-sequencing technologies allow for a more complete interrogation of the role of human variation in complex disease. The inadequate power of single variant methods to assess the role of less common variation has led to the development of numerous statistical methods for testing aggregate groups of variants for association with disease. Such endeavors pose substantial analytical challenges, however, due to the diverse array of genetic hypotheses that need to be considered. In this work, we systematically quantify and compare the performance of a panel of commonly used gene-based association methods under a range of allelic architectures, significance thresholds, locus effect sizes, sample sizes, and filters for neutral variation. We find that MiST, SKAT-O, and KBAC have the highest mean power across simulated datasets. Across all methods, however, the power to detect even loci of relatively large effect is very low at exome-wide significance thresholds for sample sizes comparable with those of ongoing sequencing studies; as such, the absence of signal in studies of a few thousand individuals does not exclude a role for rare variation in complex traits. Finally, we directly compare the results reported by different gene-based methods in order to identify their comparative advantages and disadvantages under distinct locus architectures. Our findings have implications for meaningful interpretation of both positive and negative findings in ongoing and future sequencing studies.
doi:10.1371/journal.pgen.1005165
PMCID: PMC4407972  PMID: 25906071
15.  Increased Burden of Cardiovascular Disease in Carriers of APOL1 Genetic Variants 
Circulation research  2013;114(5):845-850.
Rationale
Two distinct alleles in the gene encoding apolipoprotein L1 (APOL1), a major component of HDL, confer protection against Trypanosoma brucei rhodesiense infection and also increase risk for chronic kidney disease (CKD). Approximately 14% of African-Americans carry two APOL1 risk alleles, accounting for the high CKD burden in this population.
Objective
We tested whether APOL1 risk alleles significantly increase risk for atherosclerotic cardiovascular disease (CVD) in African-Americans.
Methods and Results
We sequenced APOL1 in 1959 randomly selected African American participants in the Jackson Heart Study (JHS) and evaluated associations between APOL1 genotypes and renal and cardiovascular phenotypes. Previously identified association between APOL1 genotypes and CKD were confirmed (p=2.4 × 10−6). Among JHS participants with two APOL1 risk alleles, we observed increased risk for CVD (50/763 events among participants without vs. 37/280 events among participants with two risk alleles; odds ratio (OR): 2.17, p=9.4 × 10−4). We replicated this novel association of APOL1 genotype with CVD in Women’s Health Initiative (WHI) participants (66/292 events among participants without vs. 37/101 events among participants with two risk alleles; OR: 1.98, p=8.37 × 10−3; JHS and WHI combined, p=8.5 × 10−5; OR: 2.12). The increased risk for CVD conferred by APOL1 alleles was robust to correction for both traditional CVD risk factors and CKD.
Conclusions
APOL1 variants contribute to atherosclerotic CVD risk, indicating a genetic component to cardiovascular health disparities in individuals of African ancestry. The considerable population of African Americans with two APOL1 risk alleles may benefit from intensive interventions to reduce CVD.
doi:10.1161/CIRCRESAHA.114.302347
PMCID: PMC3982584  PMID: 24379297
Genetics; risk factors; epidemiology; chronic kidney disease; atherosclerosis; genetic association; cardiovascular genomics; race; ethnicity
16.  Identification and Functional Characterization of G6PC2 Coding Variants Influencing Glycemic Traits Define an Effector Transcript at the G6PC2-ABCB11 Locus 
Mahajan, Anubha | Sim, Xueling | Ng, Hui Jin | Manning, Alisa | Rivas, Manuel A. | Highland, Heather M. | Locke, Adam E. | Grarup, Niels | Im, Hae Kyung | Cingolani, Pablo | Flannick, Jason | Fontanillas, Pierre | Fuchsberger, Christian | Gaulton, Kyle J. | Teslovich, Tanya M. | Rayner, N. William | Robertson, Neil R. | Beer, Nicola L. | Rundle, Jana K. | Bork-Jensen, Jette | Ladenvall, Claes | Blancher, Christine | Buck, David | Buck, Gemma | Burtt, Noël P. | Gabriel, Stacey | Gjesing, Anette P. | Groves, Christopher J. | Hollensted, Mette | Huyghe, Jeroen R. | Jackson, Anne U. | Jun, Goo | Justesen, Johanne Marie | Mangino, Massimo | Murphy, Jacquelyn | Neville, Matt | Onofrio, Robert | Small, Kerrin S. | Stringham, Heather M. | Syvänen, Ann-Christine | Trakalo, Joseph | Abecasis, Goncalo | Bell, Graeme I. | Blangero, John | Cox, Nancy J. | Duggirala, Ravindranath | Hanis, Craig L. | Seielstad, Mark | Wilson, James G. | Christensen, Cramer | Brandslund, Ivan | Rauramaa, Rainer | Surdulescu, Gabriela L. | Doney, Alex S. F. | Lannfelt, Lars | Linneberg, Allan | Isomaa, Bo | Tuomi, Tiinamaija | Jørgensen, Marit E. | Jørgensen, Torben | Kuusisto, Johanna | Uusitupa, Matti | Salomaa, Veikko | Spector, Timothy D. | Morris, Andrew D. | Palmer, Colin N. A. | Collins, Francis S. | Mohlke, Karen L. | Bergman, Richard N. | Ingelsson, Erik | Lind, Lars | Tuomilehto, Jaakko | Hansen, Torben | Watanabe, Richard M. | Prokopenko, Inga | Dupuis, Josee | Karpe, Fredrik | Groop, Leif | Laakso, Markku | Pedersen, Oluf | Florez, Jose C. | Morris, Andrew P. | Altshuler, David | Meigs, James B. | Boehnke, Michael | McCarthy, Mark I. | Lindgren, Cecilia M. | Gloyn, Anna L.
PLoS Genetics  2015;11(1):e1004876.
Genome wide association studies (GWAS) for fasting glucose (FG) and insulin (FI) have identified common variant signals which explain 4.8% and 1.2% of trait variance, respectively. It is hypothesized that low-frequency and rare variants could contribute substantially to unexplained genetic variance. To test this, we analyzed exome-array data from up to 33,231 non-diabetic individuals of European ancestry. We found exome-wide significant (P<5×10-7) evidence for two loci not previously highlighted by common variant GWAS: GLP1R (p.Ala316Thr, minor allele frequency (MAF)=1.5%) influencing FG levels, and URB2 (p.Glu594Val, MAF = 0.1%) influencing FI levels. Coding variant associations can highlight potential effector genes at (non-coding) GWAS signals. At the G6PC2/ABCB11 locus, we identified multiple coding variants in G6PC2 (p.Val219Leu, p.His177Tyr, and p.Tyr207Ser) influencing FG levels, conditionally independent of each other and the non-coding GWAS signal. In vitro assays demonstrate that these associated coding alleles result in reduced protein abundance via proteasomal degradation, establishing G6PC2 as an effector gene at this locus. Reconciliation of single-variant associations and functional effects was only possible when haplotype phase was considered. In contrast to earlier reports suggesting that, paradoxically, glucose-raising alleles at this locus are protective against type 2 diabetes (T2D), the p.Val219Leu G6PC2 variant displayed a modest but directionally consistent association with T2D risk. Coding variant associations for glycemic traits in GWAS signals highlight PCSK1, RREB1, and ZHX3 as likely effector transcripts. These coding variant association signals do not have a major impact on the trait variance explained, but they do provide valuable biological insights.
Author Summary
Understanding how FI and FG levels are regulated is important because their derangement is a feature of T2D. Despite recent success from GWAS in identifying regions of the genome influencing glycemic traits, collectively these loci explain only a small proportion of trait variance. Unlocking the biological mechanisms driving these associations has been challenging because the vast majority of variants map to non-coding sequence, and the genes through which they exert their impact are largely unknown. In the current study, we sought to increase our understanding of the physiological pathways influencing both traits using exome-array genotyping in up to 33,231 non-diabetic individuals to identify coding variants and consequently genes associated with either FG or FI levels. We identified novel association signals for both traits including the receptor for GLP-1 agonists which are a widely used therapy for T2D. Furthermore, we identified coding variants at several GWAS loci which point to the genes underlying these association signals. Importantly, we found that multiple coding variants in G6PC2 result in a loss of protein function and lower fasting glucose levels.
doi:10.1371/journal.pgen.1004876
PMCID: PMC4307976  PMID: 25625282
17.  The Role of CD133+ Cells in a Recurrent Embryonal Tumor with Abundant Neuropil and True Rosettes (ETANTR) 
Brain pathology (Zurich, Switzerland)  2013;24(1):10.1111/bpa.12079.
Embryonal tumor with abundant neuropil and true rosettes (ETANTR) is a recently described embryonal neoplasm of the central nervous system, consisting of a well-circumscribed embryonal tumor of infancy with mixed features of ependymoblastoma (multilayer ependymoblastic rosettes and pseudorosettes) and neuroblastoma (neuroblastic rosettes) in the presence of neuropil-like islands. We present the case of a young child with a very aggressive tumor that rapidly recurred after gross total resection, chemotherapy, and radiation. Prominent vascular sclerosis and circumscribed tumor led to the diagnosis of malignant astroblastoma; however, rapid recurrence and progression of this large tumor after gross total resection prompted review of the original pathology. ETANTR is histologically distinct with focal GFAP and synaptophysin expression in the presence of neuronal and ependymoblastic rosettes with focal neuropil islands. These architectural features, combined with unique chromosome 19q.13.42 amplification, confirmed the diagnosis. In this report, we describe tumor stem cell (TSC) marker CD133, CD15, and nestin alterations in ETANTR before and after chemotherapy. We found that TSC marker CD133 was richly expressed after chemotherapy in recurrent ETANTR, while CD15 is depleted compared to that expressed in the original tumor, suggesting that CD133+ cells likely survived initial treatment, further contributing to formation of the recurrent tumor.
doi:10.1111/bpa.12079
PMCID: PMC3867594  PMID: 23865520
Embryonal tumor with abundant neuropil and true rosettes; ETANTR; tumor stem cell; microRNA
18.  Clinical skills development in student-run free clinic volunteers: a multi-trait, multi-measure study 
BMC Medical Education  2014;14:250.
Background
At Wayne State University School of Medicine (WSU SOM), the Robert R. Frank Student Run Free Clinic (SRFC) is one place preclinical students can gain clinical experience. There have been no published studies to date measuring the impact of student-run free clinic (SRFC) volunteerism on clinical skills development in preclinical medical students.
Methods
Surveys were given to first year medical students at WSU SOM at the beginning and end of Year 1 to assess perception of clinical skills, including self-confidence, self-reflection, and professionalism. Scores of the Year 1 Objective Structured Clinical Exam (OSCE) were compared between SRFC volunteers and non-volunteers.
Results
There were a total of 206 (68.2%) and 80 (26.5%) survey responses at the beginning and end of Year 1, respectively. Of the 80 students, 31 (38.7%) volunteered at SRFC during Year 1. Statistically significant differences were found between time points in self-confidence (p < 0.001) in both groups. When looking at self-confidence in skills pertaining to SRFC, the difference between groups was statistically significant (p = 0.032) at both time points. A total of 302 students participated in the Year 1 OSCE, 27 (9%) of which were SRFC volunteers. No statistically significant differences were found between groups for mean score (p = 0.888) and established level of rapport (p = 0.394).
Conclusions
While this study indicated no significant differences in clinical skills in students who volunteer at the SRFC, it is a first step in attempting to measure clinical skill development outside of the structured medical school setting. The findings lend themselves to development of research designs, clinical surveys, and future studies to measure the impact of clinical volunteer opportunities on clinical skills development in future physicians.
doi:10.1186/s12909-014-0250-9
PMCID: PMC4267714  PMID: 25495286
19.  Branched chain and aromatic amino acids change acutely following two medical therapies for type 2 diabetes mellitus 
Metabolism: clinical and experimental  2013;62(12):10.1016/j.metabol.2013.07.003.
Objective
Elevated circulating levels of branched chain and aromatic amino acids (BCAA/AAAs) are associated with insulin resistance and incident type 2 diabetes (T2D). BCAA/AAAs decrease acutely during an oral glucose tolerance test (OGTT), a diagnostic test for T2D. It is unknown whether changes in BCAA/AAAs also signal an early response to commonly used medical therapies for T2D.
Materials and Methods
A liquid chromatography-mass spectrometry approach was used to measure BCAA/AAAs in 30 insulin sensitive (IS) and 30 insulin resistant (IR) subjects before and after: 1) one dose of a sulfonylurea medication, glipizide, 5 mg orally; 2) two days of twice daily metformin 500 mg orally; and 3) a 75-gram OGTT. Percent change in BCAA/AAAs was determined after each intervention.
Results
Following glipizide, which increased insulin and decreased glucose in both subject groups, BCAA/AAAs decreased in the IS subjects only (all P<0.05). Following metformin, which decreased glucose and insulin in only the IR subjects, 4 BCAA/AAAs increased in the IR subjects at or below P=0.05, and none changed in the IS subjects. Following OGTT, which increased glucose and insulin in all subjects, BCAA/AAAs decreased in all subjects (P<0.05).
Conclusions
BCAA/AAAs changed acutely during glipizide and metformin administration, and the magnitude and direction of change differed by the insulin resistance status of the individual and the intervention. These results indicate that BCAA/AAAs may be useful biomarkers for monitoring the early response to therapeutic interventions for T2D.
doi:10.1016/j.metabol.2013.07.003
PMCID: PMC3833885  PMID: 23953891
branched chain amino acids; aromatic amino acids
20.  From FastQ data to high confidence variant calls: the Genome Analysis Toolkit best practices pipeline 
This unit describes how to use BWA and the Genome Analysis Toolkit (GATK) to map genome sequencing data to a reference and produce high-quality variant calls that can be used in downstream analyses. The complete workflow includes the core NGS data processing steps that are necessary to make the raw data suitable for analysis by the GATK, as well as the key methods involved in variant discovery using the GATK.
doi:10.1002/0471250953.bi1110s43
PMCID: PMC4243306  PMID: 25431634
NGS; WGS; exome; variant detection; genotyping
21.  Evaluating empirical bounds on complex disease genetic architecture 
Nature genetics  2013;45(12):1418-1427.
The genetic architecture of human diseases governs the success of genetic mapping and the future of personalized medicine. Although numerous studies have queried the genetic basis of common disease, contradictory hypotheses have been advocated about features of genetic architecture (e.g., the contribution of rare vs. common variants). We developed an integrated simulation framework, calibrated to empirical data, to enable systematic evaluation of such hypotheses. For type 2 diabetes (T2D), two simple parameters – (a) the target size for causal mutation and (b) the coupling between selection and phenotypic effect – define a broad space of architectures. While extreme models are excluded, many models remain consistent with epidemiology, linkage, and genome-wide association studies for T2D, including those where rare variants explain little (<25%) or most (>80%) of heritability. Ongoing sequencing and genotyping studies will further constrain architecture, but very large samples (e.g., >250K unselected individuals) will be required to localize most of the heritability underlying traits like T2D.
doi:10.1038/ng.2804
PMCID: PMC4158716  PMID: 24141362
22.  Distribution and Medical Impact of Loss-of-Function Variants in the Finnish Founder Population 
PLoS Genetics  2014;10(7):e1004494.
Exome sequencing studies in complex diseases are challenged by the allelic heterogeneity, large number and modest effect sizes of associated variants on disease risk and the presence of large numbers of neutral variants, even in phenotypically relevant genes. Isolated populations with recent bottlenecks offer advantages for studying rare variants in complex diseases as they have deleterious variants that are present at higher frequencies as well as a substantial reduction in rare neutral variation. To explore the potential of the Finnish founder population for studying low-frequency (0.5–5%) variants in complex diseases, we compared exome sequence data on 3,000 Finns to the same number of non-Finnish Europeans and discovered that, despite having fewer variable sites overall, the average Finn has more low-frequency loss-of-function variants and complete gene knockouts. We then used several well-characterized Finnish population cohorts to study the phenotypic effects of 83 enriched loss-of-function variants across 60 phenotypes in 36,262 Finns. Using a deep set of quantitative traits collected on these cohorts, we show 5 associations (p<5×10−8) including splice variants in LPA that lowered plasma lipoprotein(a) levels (P = 1.5×10−117). Through accessing the national medical records of these participants, we evaluate the LPA finding via Mendelian randomization and confirm that these splice variants confer protection from cardiovascular disease (OR = 0.84, P = 3×10−4), demonstrating for the first time the correlation between very low levels of LPA in humans with potential therapeutic implications for cardiovascular diseases. More generally, this study articulates substantial advantages for studying the role of rare variation in complex phenotypes in founder populations like the Finns and by combining a unique population genetic history with data from large population cohorts and centralized research access to National Health Registers.
Author Summary
We explored the coding regions of 3,000 Finnish individuals with 3,000 non-Finnish Europeans (NFEs) using whole-exome sequence data, in order to understand how an individual from a bottlenecked population might differ from an individual from an out-bred population. We provide empirical evidence that there are more rare and low-frequency deleterious alleles in Finns compared to NFEs, such that an average Finn has almost twice as many low-frequency complete knockouts of a gene. As such, we hypothesized that some of these low-frequency loss-of-function variants might have important medical consequences in humans and genotyped 83 of these variants in 36,000 Finns. In doing so, we discovered that completely knocking out the TSFM gene might result in inviability or a very severe phenotype in humans and that knocking out the LPA gene might confer protection against coronary heart diseases, suggesting that LPA is likely to be a good potential therapeutic target.
doi:10.1371/journal.pgen.1004494
PMCID: PMC4117444  PMID: 25078778
23.  Comparing strategies to fine map the association of common SNPs on chromosome 9p21 to Type 2 Diabetes and Myocardial Infarction 
Nature genetics  2011;43(8):801-805.
Non-coding variants at human chromosome 9p21 near CDKN2A and CDKN2B are associated with type 2 diabetes (T2D)1-4, myocardial infarction (MI)5-7, aneurysm8, vertical cup disc ratio9, and at least five cancers10-16. We compared approaches to more comprehensively assess genetic variation in the region. We performed targeted sequencing at high coverage in 47 individuals and compared the results to pilot data from the 1000 Genomes Project. We imputed variants into T2D and MI cohorts directly from targeted sequencing, from a genotyped reference panel derived from sequencing, and from 1000 Genomes low-coverage data. Common polymorphisms were captured similarly by all strategies. Imputation of intermediate frequency polymorphisms required a higher density of tag SNPs in disease samples than available on first generation Genome Wide Association Study (GWAS) arrays. Association analyses identified more comprehensive sets of variants demonstrating equivalent statistical association to T2D or MI, but did not identify stronger associations the original GWAS signals.
doi:10.1038/ng.871
PMCID: PMC4096898  PMID: 21775993
24.  Assessing the phenotypic effects in the general population of rare variants in genes for a dominant mendelian form of diabetes 
Nature genetics  2013;45(11):1380-1385.
Genome sequencing can identify individuals in the general population who harbor rare coding variants in genes for Mendelian disorders1–7 – and who consequently may have increased disease risk. However, previous studies of rare variants in phenotypically extreme individuals have ascertainment bias and may demonstrate inflated effect size estimates8–12. We sequenced seven genes for maturity-onset diabetes of the young (MODY)13 in well-phenotyped population samples14,15 (n=4,003). Rare variants were filtered according to prediction criteria used to identify disease-causing mutations: i) previously-reported in MODY, and ii) stringent de novo thresholds satisfied (rare, conserved, protein damaging). Approximately 1.5% and 0.5% of randomly selected Framingham and Jackson Heart Study individuals carried variants from these two classes, respectively. However, the vast majority of carriers remained euglycemic through middle age. Accurate estimates of variant effect sizes from population-based sequencing are needed to avoid falsely predicting a significant fraction of individuals as at risk for MODY or other Mendelian diseases.
doi:10.1038/ng.2794
PMCID: PMC4051627  PMID: 24097065
25.  Loss-of-function mutations in SLC30A8 protect against type 2 diabetes 
Flannick, Jason | Thorleifsson, Gudmar | Beer, Nicola L. | Jacobs, Suzanne B. R. | Grarup, Niels | Burtt, Noël P. | Mahajan, Anubha | Fuchsberger, Christian | Atzmon, Gil | Benediktsson, Rafn | Blangero, John | Bowden, Don W. | Brandslund, Ivan | Brosnan, Julia | Burslem, Frank | Chambers, John | Cho, Yoon Shin | Christensen, Cramer | Douglas, Desirée A. | Duggirala, Ravindranath | Dymek, Zachary | Farjoun, Yossi | Fennell, Timothy | Fontanillas, Pierre | Forsén, Tom | Gabriel, Stacey | Glaser, Benjamin | Gudbjartsson, Daniel F. | Hanis, Craig | Hansen, Torben | Hreidarsson, Astradur B. | Hveem, Kristian | Ingelsson, Erik | Isomaa, Bo | Johansson, Stefan | Jørgensen, Torben | Jørgensen, Marit Eika | Kathiresan, Sekar | Kong, Augustine | Kooner, Jaspal | Kravic, Jasmina | Laakso, Markku | Lee, Jong-Young | Lind, Lars | Lindgren, Cecilia M | Linneberg, Allan | Masson, Gisli | Meitinger, Thomas | Mohlke, Karen L | Molven, Anders | Morris, Andrew P. | Potluri, Shobha | Rauramaa, Rainer | Ribel-Madsen, Rasmus | Richard, Ann-Marie | Rolph, Tim | Salomaa, Veikko | Segrè, Ayellet V. | Skärstrand, Hanna | Steinthorsdottir, Valgerdur | Stringham, Heather M. | Sulem, Patrick | Tai, E Shyong | Teo, Yik Ying | Teslovich, Tanya | Thorsteinsdottir, Unnur | Trimmer, Jeff K. | Tuomi, Tiinamaija | Tuomilehto, Jaakko | Vaziri-Sani, Fariba | Voight, Benjamin F. | Wilson, James G. | Boehnke, Michael | McCarthy, Mark I. | Njølstad, Pål R. | Pedersen, Oluf | Groop, Leif | Cox, David R. | Stefansson, Kari | Altshuler, David
Nature genetics  2014;46(4):357-363.
Loss-of-function mutations protective against human disease provide in vivo validation of therapeutic targets1,2,3, yet none are described for type 2 diabetes (T2D). Through sequencing or genotyping ~150,000 individuals across five ethnicities, we identified 12 rare protein-truncating variants in SLC30A8, which encodes an islet zinc transporter (ZnT8)4 and harbors a common variant (p.Trp325Arg) associated with T2D risk, glucose, and proinsulin levels5–7. Collectively, protein-truncating variant carriers had 65% reduced T2D risk (p=1.7×10−6), and non-diabetic Icelandic carriers of a frameshift variant (p.Lys34SerfsX50) demonstrated reduced glucose levels (−0.17 s.d., p=4.6×10−4). The two most common protein-truncating variants (p.Arg138X and p.Lys34SerfsX50) individually associate with T2D protection and encode unstable ZnT8 proteins. Previous functional study of SLC30A8 suggested reduced zinc transport increases T2D risk8,9, yet phenotypic heterogeneity was observed in rodent Slc30a8 knockouts10–15. Contrastingly, loss-of-function mutations in humans provide strong evidence that SLC30A8 haploinsufficiency protects against T2D, proposing ZnT8 inhibition as a therapeutic strategy in T2D prevention.
doi:10.1038/ng.2915
PMCID: PMC4051628  PMID: 24584071

Results 1-25 (118)