Genetic Epidemiology Network of Arteriopathy (GENOA)

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Genetic Epidemiology Network of Arteriopathy (GENOA) Genetic Epidemiology Network of Arteriopathy (GENOA) Study Description The Genetic Epidemiology Network of Arteriopathy (GENOA) From its inception in 1995, GENOA's long-term objective was to elucidate the genetics of hypertension and its arteriosclerotic target-organ damage, including both atherosclerotic (macrovascular) and arteriolosclerotic (microvascular) complications involving the heart, brain, kidneys, and peripheral arteries. Two GENOA cohorts were originally ascertained (1995-2000) through sibships in which at least 2 siblings had essential hypertension diagnosed prior to 60 years of age. All siblings in the sibship were invited to participate, both normotensive and hypertensive. These include non-Hispanic White Americans from Rochester, MN (n =1583 at the 1st exam) and African Americans from Jackson, MS (N=1854 at the 1st exam). A third Hispanic American cohort from Starr County, TX, was ascertained through diabetic rather than hypertensive sibships (N=1812). The Hispanic American cohort is not included in this genetic analysis because no genome-wide genotype data is currently available for this cohort. Exclusion criteria for the white and African American cohorts were secondary hypertension, alcoholism or drug abuse, pregnancy, insulin-dependent diabetes mellitus, or active malignancy. The GENOA data consists of biological samples (DNA, serum, urine) as well as demographic, anthropometric, environmental, clinical, biochemical, physiological, and genetic data for understanding the genetic predictors of diseases of the heart, brain, kidney, and peripheral arteries. Data were collected during two phases (Phase I from 1995-2000, Phase II from 2001-2004) and multiple ancillary studies (eg., chronic kidney disease assessments, brain MRIs, 24-hour urine and blood pressure assessments, etc). Written informed consent was obtained from all subjects and approval was granted by participating institutional review boards. Given that our informed consent documentation limits data sharing to GENOA investigators and our collaborators, we are unable to make individual-level GENOA phenotype and genotype data available on dbGAP at this time. We are working on this consent issue. However, we have made our analysis results available and we fully welcome collaboration with researchers that would like to include the GENOA sample in their analyses. We can easily allow transfer of the individual-level data with an appropriate Data Transfer Agreement. If you would like to collaborate with GENOA, please contact: Sharon L.R. Kardia, Ph.D. Professor and Chair, Department of Epidemiology School of Public Health, University of Michigan 1415 Washington Heights, Room 4659 Ann Arbor, MI 48109 (734) 647-1029 [email protected] Family Blood Pressure Program (FBPP) GENOA is one of four research networks that form the NHLBI Family Blood Pressure Program (FBPP). GENOA’s parent program, the FBPP, is an unprecedented collaboration to identify genes influencing blood pressure (BP) levels, hypertension, and its target-organ damage. This program has conducted over 21,000 physical examinations, assembled a shared database of several hundred BP and hypertension-related phenotypic measurements, completed genome-wide linkage analyses for BP, hypertension, and hypertension associated risk factors and complications, and published over 130 manuscripts on program findings. The FBPP emerged from what was initially funded as four independent networks of investigators (HyperGEN, GenNet, SAPPHIRe and GENOA) competing to identify genetic determinants of hypertension in multiple ethnic groups. Realizing the greater likelihood of success through collaboration, the investigators began working together during the first funding cycle (1995-2000) and formalized this arrangement in the second cycle (2000-2005), creating a single confederation with program-wide and network-specific goals. Hypertension case definition and exclusion criteria for GENOA Individuals in GENOA belong to sibships identified in which at least two siblings had essential hypertension diagnosed prior to 60 years of age. After identification of the initial pairs of hypertensive siblings, all siblings in the sibship were invited to participate regardless of hypertension status. Hypertension case definition: Essential hypertension diagnosed prior to age 60 years of age, defined as: 1) average of the last 2 out of 3 systolic BP readings ≥ 140mmHg, or 2) an average of the last 2 out of 3 diastolic BP readings ≥ 90 mmHg, or 3) previous diagnosis of hypertension and antihypertensive medication prescribed by a physician to be taken daily during the last month. Exclusion criteria: Pregnancy or breast feeding, Type I diabetes mellitus (juvenile onset, insulin dependent), diagnosis of hypertension ≥ 60 yrs of age, or secondary causes of hypertension including but not limited to prior knowledge of renal parenchymal disease or serum creatinine ≥ 2.5 mg/dL, renal vascular disease, primary aldosteronism, pheochromocytoma, coarctation of aorta, hypertension associated with current use of oral contraceptive agents, prescription or non-prescription drugs, or active alcohol abuse. Sample size Non-Hispanic whites from Rochester, MN Phase I: N=1,583 Phase II: N=1,241 African Americans from Jackson, MS Phase I: N=1,854 Phase II: N=1,482 Key GENOA Publications Daniels PR, Kardia SL, Hanis CL, Brown CA, Hutchinson R, Boerwinkle E, Turner ST, Genetic Epidemiology Network of Arteriopathy study. Familial Aggregation of Hypertension Treatment and Control in the Genetic Epidemiology Network of Arteriopathy (GENOA) Study. Am J Med 2004; 116(10): 676-681. PMID: 15121494. FBPP Investigators. Multi-Center Genetic Study of Hypertension: The Family Blood Pressure Program (FBPP). Hypertension 2002; 39(1): 3-9. PMID: 11799070. Kardia SL, Greene MT, Boerwinkle E, Turner ST, Kullo IJ. Investigating the complex genetic architecture of ankle- brachial index, a measure of peripheral arterial disease, in non-Hispanic whites. BMC Med Genomics 2008; 1:16. PMID: 18482449. Khawaja FJ, Bailey KR, Turner ST, Kardia SL, Mosley TH Jr, Kullo IJ. Association of novel risk factors with the ankle brachial index in African American and non-Hispanic white populations. Mayo Clin Proc. 2007; 82(6): 709-16. PMID: 17550751. Knopman DS, Mosley TH Jr, Bailey KR, Jack CR Jr, Schwartz GL, Turner ST. Associations of microalbuminuria with brain atrophy and white matter hyperintensities in hypertensive sibships. J Neurol Sci 2008; 271(1-2): 53-60. PMID: 18442832. Lange LA, Lange EM, Bielak LF, Langefeld CD, Kardia SL, Royston P, Turner ST, Sheedy PF 2nd, Boerwinkle E, Peyser PA. Autosomal genome-wide scan for coronary artery calcification loci in sibships at high risk for hypertension. Arterioscler Thromb Vasc Biol 2002; 22(3): 418-23. PMID: 11884284. Meyers KJ, Mosley TH, Fox E, Boerwinkle E, Arnett DK, Devereux RB, Kardia SL. Genetic variations associated with echocardiographic left ventricular traits in hypertensive blacks. Hypertension 2007; 49(5): 992-9. PMID: 17339538. Rule AD, de Andrade M, Matsumoto M, Mosley TH, Kardia S, Turner ST. Association between SLC2A9 transporter gene variants and uric acid phenotypes in African American and white families. Rheumatology (Oxford) 2010; Dec 24. [Epub ahead of print] PMID: 21186168. Smith JA, Turner ST, Sun YV, Fornage M, Kelly RJ, Mosley TH, Jack CR, Kullo IJ, Kardia SL. Complexity in the genetic architecture of leukoaraiosis in hypertensive sibships from the GENOA Study. BMC Med Genomics 2009; 2:16. PMID: 19351393. Turner ST, Kardia SL, Mosley TH, Rule AD, Boerwinkle E, de Andrade M. Influence of genomic loci on measures of chronic kidney disease in hypertensive sibships. J Am Soc Nephrol 2006; 17(7): 2048-55. PMID: 16775034. Turner ST, Fornage M, Jack CR Jr, Mosley TH, Knopman DS, Kardia SL, Boerwinkle E, de Andrade M. Genomic susceptibility Loci for brain atrophy, ventricular volume, and leukoaraiosis in hypertensive sibships. Arch Neurol 2009; 66(7): 847-57. PMID: 19597086. Outcome Measures Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), and Pulse Pressure (PP) Blood pressure measures were obtained at the Phase I examination. Examinations were conducted in the morning after an overnight fast of at least eight hours. Using random zero sphygmomanometers and cuffs appropriate for arm size, three readings of blood pressure were taken in the right arm after the participant rested in the sitting position for at least five minutes; the last two readings were averaged for the analyses. Pulse pressure (PP) was calculated as the difference between the average systolic and diastolic blood pressures. Body Mass Index (BMI) Body mass index (BMI) was calculated using height and weight measures obtained at the Phase I examination. Height was measured by stadiometer, weight by electronic balance, and body mass index (BMI) was calculated as weight in kilograms divided by the square of height in meters. Ankle-Brachial Index (ABI) Ankle-brachial index (ABI) was measured during the Phase II examination. Measurements were taken while participants were in the supine position following a 5-min rest. Appropriately sized BP cuffs were placed on each arm and ankle, and a Doppler ultrasonic instrument (Medisonics, Minneapolis MN) was used to detect each pulse. The cuff was inflated to 10 mm Hg above SBP and deflated at 2 mm Hg/s. The first reappearance of the pulse was taken as the SBP. To calculate ABI, the SBP at each ankle site (posterior tibial and dorsalis pedis) was divided by the higher of the 2 brachial pressures. The lowest
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