TY - JOUR T1 - Diagnostic Yield and Clinical Utility of Sequencing Familial Hypercholesterolemia Genes in Patients With Severe Hypercholesterolemia. JF - J Am Coll Cardiol Y1 - 2016 A1 - Khera, Amit V A1 - Won, Hong-Hee A1 - Peloso, Gina M A1 - Lawson, Kim S A1 - Bartz, Traci M A1 - Deng, Xuan A1 - van Leeuwen, Elisabeth M A1 - Natarajan, Pradeep A1 - Emdin, Connor A A1 - Bick, Alexander G A1 - Morrison, Alanna C A1 - Brody, Jennifer A A1 - Gupta, Namrata A1 - Nomura, Akihiro A1 - Kessler, Thorsten A1 - Duga, Stefano A1 - Bis, Joshua C A1 - van Duijn, Cornelia M A1 - Cupples, L Adrienne A1 - Psaty, Bruce A1 - Rader, Daniel J A1 - Danesh, John A1 - Schunkert, Heribert A1 - McPherson, Ruth A1 - Farrall, Martin A1 - Watkins, Hugh A1 - Lander, Eric A1 - Wilson, James G A1 - Correa, Adolfo A1 - Boerwinkle, Eric A1 - Merlini, Piera Angelica A1 - Ardissino, Diego A1 - Saleheen, Danish A1 - Gabriel, Stacey A1 - Kathiresan, Sekar AB -

BACKGROUND: Approximately 7% of American adults have severe hypercholesterolemia (untreated low-density lipoprotein [LDL] cholesterol ≥190 mg/dl), which may be due to familial hypercholesterolemia (FH). Lifelong LDL cholesterol elevations in FH mutation carriers may confer coronary artery disease (CAD) risk beyond that captured by a single LDL cholesterol measurement.

OBJECTIVES: This study assessed the prevalence of an FH mutation among those with severe hypercholesterolemia and determined whether CAD risk varies according to mutation status beyond the observed LDL cholesterol level.

METHODS: Three genes causative for FH (LDLR, APOB, and PCSK9) were sequenced in 26,025 participants from 7 case-control studies (5,540 CAD case subjects, 8,577 CAD-free control subjects) and 5 prospective cohort studies (11,908 participants). FH mutations included loss-of-function variants in LDLR, missense mutations in LDLR predicted to be damaging, and variants linked to FH in ClinVar, a clinical genetics database.

RESULTS: Among 20,485 CAD-free control and prospective cohort participants, 1,386 (6.7%) had LDL cholesterol ≥190 mg/dl; of these, only 24 (1.7%) carried an FH mutation. Within any stratum of observed LDL cholesterol, risk of CAD was higher among FH mutation carriers than noncarriers. Compared with a reference group with LDL cholesterol <130 mg/dl and no mutation, participants with LDL cholesterol ≥190 mg/dl and no FH mutation had a 6-fold higher risk for CAD (odds ratio: 6.0; 95% confidence interval: 5.2 to 6.9), whereas those with both LDL cholesterol ≥190 mg/dl and an FH mutation demonstrated a 22-fold increased risk (odds ratio: 22.3; 95% confidence interval: 10.7 to 53.2). In an analysis of participants with serial lipid measurements over many years, FH mutation carriers had higher cumulative exposure to LDL cholesterol than noncarriers.

CONCLUSIONS: Among participants with LDL cholesterol ≥190 mg/dl, gene sequencing identified an FH mutation in <2%. However, for any observed LDL cholesterol, FH mutation carriers had substantially increased risk for CAD.

VL - 67 IS - 22 U1 - http://www.ncbi.nlm.nih.gov/pubmed/27050191?dopt=Abstract ER - TY - JOUR T1 - Exome Genotyping Identifies Pleiotropic Variants Associated with Red Blood Cell Traits. JF - Am J Hum Genet Y1 - 2016 A1 - Chami, Nathalie A1 - Chen, Ming-Huei A1 - Slater, Andrew J A1 - Eicher, John D A1 - Evangelou, Evangelos A1 - Tajuddin, Salman M A1 - Love-Gregory, Latisha A1 - Kacprowski, Tim A1 - Schick, Ursula M A1 - Nomura, Akihiro A1 - Giri, Ayush A1 - Lessard, Samuel A1 - Brody, Jennifer A A1 - Schurmann, Claudia A1 - Pankratz, Nathan A1 - Yanek, Lisa R A1 - Manichaikul, Ani A1 - Pazoki, Raha A1 - Mihailov, Evelin A1 - Hill, W David A1 - Raffield, Laura M A1 - Burt, Amber A1 - Bartz, Traci M A1 - Becker, Diane M A1 - Becker, Lewis C A1 - Boerwinkle, Eric A1 - Bork-Jensen, Jette A1 - Bottinger, Erwin P A1 - O'Donoghue, Michelle L A1 - Crosslin, David R A1 - de Denus, Simon A1 - Dubé, Marie-Pierre A1 - Elliott, Paul A1 - Engström, Gunnar A1 - Evans, Michele K A1 - Floyd, James S A1 - Fornage, Myriam A1 - Gao, He A1 - Greinacher, Andreas A1 - Gudnason, Vilmundur A1 - Hansen, Torben A1 - Harris, Tamara B A1 - Hayward, Caroline A1 - Hernesniemi, Jussi A1 - Highland, Heather M A1 - Hirschhorn, Joel N A1 - Hofman, Albert A1 - Irvin, Marguerite R A1 - Kähönen, Mika A1 - Lange, Ethan A1 - Launer, Lenore J A1 - Lehtimäki, Terho A1 - Li, Jin A1 - Liewald, David C M A1 - Linneberg, Allan A1 - Liu, Yongmei A1 - Lu, Yingchang A1 - Lyytikäinen, Leo-Pekka A1 - Mägi, Reedik A1 - Mathias, Rasika A A1 - Melander, Olle A1 - Metspalu, Andres A1 - Mononen, Nina A1 - Nalls, Mike A A1 - Nickerson, Deborah A A1 - Nikus, Kjell A1 - O'Donnell, Chris J A1 - Orho-Melander, Marju A1 - Pedersen, Oluf A1 - Petersmann, Astrid A1 - Polfus, Linda A1 - Psaty, Bruce M A1 - Raitakari, Olli T A1 - Raitoharju, Emma A1 - Richard, Melissa A1 - Rice, Kenneth M A1 - Rivadeneira, Fernando A1 - Rotter, Jerome I A1 - Schmidt, Frank A1 - Smith, Albert Vernon A1 - Starr, John M A1 - Taylor, Kent D A1 - Teumer, Alexander A1 - Thuesen, Betina H A1 - Torstenson, Eric S A1 - Tracy, Russell P A1 - Tzoulaki, Ioanna A1 - Zakai, Neil A A1 - Vacchi-Suzzi, Caterina A1 - van Duijn, Cornelia M A1 - van Rooij, Frank J A A1 - Cushman, Mary A1 - Deary, Ian J A1 - Velez Edwards, Digna R A1 - Vergnaud, Anne-Claire A1 - Wallentin, Lars A1 - Waterworth, Dawn M A1 - White, Harvey D A1 - Wilson, James G A1 - Zonderman, Alan B A1 - Kathiresan, Sekar A1 - Grarup, Niels A1 - Esko, Tõnu A1 - Loos, Ruth J F A1 - Lange, Leslie A A1 - Faraday, Nauder A1 - Abumrad, Nada A A1 - Edwards, Todd L A1 - Ganesh, Santhi K A1 - Auer, Paul L A1 - Johnson, Andrew D A1 - Reiner, Alexander P A1 - Lettre, Guillaume AB -

Red blood cell (RBC) traits are important heritable clinical biomarkers and modifiers of disease severity. To identify coding genetic variants associated with these traits, we conducted meta-analyses of seven RBC phenotypes in 130,273 multi-ethnic individuals from studies genotyped on an exome array. After conditional analyses and replication in 27,480 independent individuals, we identified 16 new RBC variants. We found low-frequency missense variants in MAP1A (rs55707100, minor allele frequency [MAF] = 3.3%, p = 2 × 10(-10) for hemoglobin [HGB]) and HNF4A (rs1800961, MAF = 2.4%, p < 3 × 10(-8) for hematocrit [HCT] and HGB). In African Americans, we identified a nonsense variant in CD36 associated with higher RBC distribution width (rs3211938, MAF = 8.7%, p = 7 × 10(-11)) and showed that it is associated with lower CD36 expression and strong allelic imbalance in ex vivo differentiated human erythroblasts. We also identified a rare missense variant in ALAS2 (rs201062903, MAF = 0.2%) associated with lower mean corpuscular volume and mean corpuscular hemoglobin (p < 8 × 10(-9)). Mendelian mutations in ALAS2 are a cause of sideroblastic anemia and erythropoietic protoporphyria. Gene-based testing highlighted three rare missense variants in PKLR, a gene mutated in Mendelian non-spherocytic hemolytic anemia, associated with HGB and HCT (SKAT p < 8 × 10(-7)). These rare, low-frequency, and common RBC variants showed pleiotropy, being also associated with platelet, white blood cell, and lipid traits. Our association results and functional annotation suggest the involvement of new genes in human erythropoiesis. We also confirm that rare and low-frequency variants play a role in the architecture of complex human traits, although their phenotypic effect is generally smaller than originally anticipated.

VL - 99 IS - 1 U1 - http://www.ncbi.nlm.nih.gov/pubmed/27346685?dopt=Abstract ER - TY - JOUR T1 - Platelet-Related Variants Identified by Exomechip Meta-analysis in 157,293 Individuals. JF - Am J Hum Genet Y1 - 2016 A1 - Eicher, John D A1 - Chami, Nathalie A1 - Kacprowski, Tim A1 - Nomura, Akihiro A1 - Chen, Ming-Huei A1 - Yanek, Lisa R A1 - Tajuddin, Salman M A1 - Schick, Ursula M A1 - Slater, Andrew J A1 - Pankratz, Nathan A1 - Polfus, Linda A1 - Schurmann, Claudia A1 - Giri, Ayush A1 - Brody, Jennifer A A1 - Lange, Leslie A A1 - Manichaikul, Ani A1 - Hill, W David A1 - Pazoki, Raha A1 - Elliot, Paul A1 - Evangelou, Evangelos A1 - Tzoulaki, Ioanna A1 - Gao, He A1 - Vergnaud, Anne-Claire A1 - Mathias, Rasika A A1 - Becker, Diane M A1 - Becker, Lewis C A1 - Burt, Amber A1 - Crosslin, David R A1 - Lyytikäinen, Leo-Pekka A1 - Nikus, Kjell A1 - Hernesniemi, Jussi A1 - Kähönen, Mika A1 - Raitoharju, Emma A1 - Mononen, Nina A1 - Raitakari, Olli T A1 - Lehtimäki, Terho A1 - Cushman, Mary A1 - Zakai, Neil A A1 - Nickerson, Deborah A A1 - Raffield, Laura M A1 - Quarells, Rakale A1 - Willer, Cristen J A1 - Peloso, Gina M A1 - Abecasis, Goncalo R A1 - Liu, Dajiang J A1 - Deloukas, Panos A1 - Samani, Nilesh J A1 - Schunkert, Heribert A1 - Erdmann, Jeanette A1 - Fornage, Myriam A1 - Richard, Melissa A1 - Tardif, Jean-Claude A1 - Rioux, John D A1 - Dubé, Marie-Pierre A1 - de Denus, Simon A1 - Lu, Yingchang A1 - Bottinger, Erwin P A1 - Loos, Ruth J F A1 - Smith, Albert Vernon A1 - Harris, Tamara B A1 - Launer, Lenore J A1 - Gudnason, Vilmundur A1 - Velez Edwards, Digna R A1 - Torstenson, Eric S A1 - Liu, Yongmei A1 - Tracy, Russell P A1 - Rotter, Jerome I A1 - Rich, Stephen S A1 - Highland, Heather M A1 - Boerwinkle, Eric A1 - Li, Jin A1 - Lange, Ethan A1 - Wilson, James G A1 - Mihailov, Evelin A1 - Mägi, Reedik A1 - Hirschhorn, Joel A1 - Metspalu, Andres A1 - Esko, Tõnu A1 - Vacchi-Suzzi, Caterina A1 - Nalls, Mike A A1 - Zonderman, Alan B A1 - Evans, Michele K A1 - Engström, Gunnar A1 - Orho-Melander, Marju A1 - Melander, Olle A1 - O'Donoghue, Michelle L A1 - Waterworth, Dawn M A1 - Wallentin, Lars A1 - White, Harvey D A1 - Floyd, James S A1 - Bartz, Traci M A1 - Rice, Kenneth M A1 - Psaty, Bruce M A1 - Starr, J M A1 - Liewald, David C M A1 - Hayward, Caroline A1 - Deary, Ian J A1 - Greinacher, Andreas A1 - Völker, Uwe A1 - Thiele, Thomas A1 - Völzke, Henry A1 - van Rooij, Frank J A A1 - Uitterlinden, André G A1 - Franco, Oscar H A1 - Dehghan, Abbas A1 - Edwards, Todd L A1 - Ganesh, Santhi K A1 - Kathiresan, Sekar A1 - Faraday, Nauder A1 - Auer, Paul L A1 - Reiner, Alex P A1 - Lettre, Guillaume A1 - Johnson, Andrew D AB -

Platelet production, maintenance, and clearance are tightly controlled processes indicative of platelets' important roles in hemostasis and thrombosis. Platelets are common targets for primary and secondary prevention of several conditions. They are monitored clinically by complete blood counts, specifically with measurements of platelet count (PLT) and mean platelet volume (MPV). Identifying genetic effects on PLT and MPV can provide mechanistic insights into platelet biology and their role in disease. Therefore, we formed the Blood Cell Consortium (BCX) to perform a large-scale meta-analysis of Exomechip association results for PLT and MPV in 157,293 and 57,617 individuals, respectively. Using the low-frequency/rare coding variant-enriched Exomechip genotyping array, we sought to identify genetic variants associated with PLT and MPV. In addition to confirming 47 known PLT and 20 known MPV associations, we identified 32 PLT and 18 MPV associations not previously observed in the literature across the allele frequency spectrum, including rare large effect (FCER1A), low-frequency (IQGAP2, MAP1A, LY75), and common (ZMIZ2, SMG6, PEAR1, ARFGAP3/PACSIN2) variants. Several variants associated with PLT/MPV (PEAR1, MRVI1, PTGES3) were also associated with platelet reactivity. In concurrent BCX analyses, there was overlap of platelet-associated variants with red (MAP1A, TMPRSS6, ZMIZ2) and white (PEAR1, ZMIZ2, LY75) blood cell traits, suggesting common regulatory pathways with shared genetic architecture among these hematopoietic lineages. Our large-scale Exomechip analyses identified previously undocumented associations with platelet traits and further indicate that several complex quantitative hematological, lipid, and cardiovascular traits share genetic factors.

VL - 99 IS - 1 U1 - http://www.ncbi.nlm.nih.gov/pubmed/27346686?dopt=Abstract ER -