Detection, evaluation, and treatment of high blood cholesterol in adults (Adult Treatment Panel III)

CHAPTER 24 – Evolution of Protein Molecules

So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Human biochemical genetics

I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

Principles of Neural Science

Appendix I: List of Statistical Fact Sheets. URL: http://www.americanheart.org/presenter.jhtml?identifier=2007

We wish to thank Drs Brian Eigel and Michael Wolz for their valuable comments and contributions. We would like to acknowledge Tim Anderson and Tom Schneider for their editorial contributions and Karen Modesitt for her administrative assistance.

Disclosures 



View this table:







View this table:







View this table:





# Summary {#article-title-2}

Each year, the American Heart Association, in conjunction with the Centers for Disease Control and Prevention, the National Institutes of Health, and other government agencies, brings together the most up-to-date statistics on heart disease, stroke, other vascular diseases, and their risk factors and presents them in its Heart Disease and Stroke Statistical Update. The Statistical Update is a valuable resource for researchers, clinicians, healthcare policy makers, media professionals, the lay public, and many others who seek the best national data available on disease …

Heart Disease and Stroke Statistics—2010 Update A Report From the American Heart Association

Objective. —To determine the risk of elevated total homocysteine (tHcy) levels for arteriosclerotic vascular disease, estimate the reduction of tHcy by folic acid, and calculate the potential reduction of coronary artery disease (CAD) mortality by increasing folic acid intake. Data Sources. —MEDLINE search for meta-analysis of 27 studies relating homocysteine to arteriosclerotic vascular disease and 11 studies of folic acid effects on tHcy levels. Study Selection and Data Extraction. —Studies dealing with CAD, cerebrovascular disease, and peripheral arterial vascular disease were selected. Three prospective and six population-based case-control studies were considered of high quality. Five cross-sectional and 13 other case-control studies were also included. Causality of tHcy's role in the pathogenesis of vascular disease was inferred because of consistency across studies by different investigators using different methods in different populations. Data Synthesis. —Elevations in tHcy were considered an independent graded risk factor for arteriosclerotic vascular diseases. The odds ratio (OR) for CAD of a 5-μmol/L tHcy increment is 1.6(95% confidence interval [Cl], 1.4 to 1.7) for men and 1.8 (95% Cl, 1.3 to 1.9) for women. A total of 10% of the population's CAD risk appears attributable to tHcy. The OR for cerebrovascular disease (5-μmol/L tHcy increment) is 1.5 (95% Cl, 1.3 to 1.9). Peripheral arterial disease also showed a strong association. Increased folic acid intake (approximately 200 μg/d) reduces tHcy levels by approximately 4 μmol/L. Assuming that lower tHcy levels decrease CAD mortality, we calculated the effect of (1) increased dietary folate, (2) supplementation by tablets, and (3) grain fortification. Under different assumptions, 13 500 to 50 000 CAD deaths annually could be avoided; fortification of food had the largest impact. Conclusions. —A 5-μmol/L tHcy increment elevates CAD risk by as much as cholesterol increases of 0.5 mmol/L (20 mg/dL). Higher folic acid intake by reducing tHcy levels promises to prevent arteriosclerotic vascular disease. Clinical trials are urgently needed. Concerns about masking cobalamin deficiency by folic acid could be lessened by adding 1 mg of cobalamin to folic acid supplements. ( JAMA . 1995;274:1049-1057)

https://jamanetwork.com/journals/jama/articlepdf/389728/jama_274_13_028.pdf

A quantitative assessment of plasma homocysteine as a risk factor for vascular disease. Probable benefits of increasing folic acid intakes

To assess the genetics of hyperlipidemia in coronary heart disease, family studies were carried out in 2520 relatives and spouses of 176 survivors of myocardial infarction, including 149 hyperlipidemic and 27 normolipidemic individuals. The distribution of fasting plasma cholesterol and triglyceride values in relatives, together with segregation analyses, suggested the presence of five distinct lipid disorders. Three of these-familial hypercholesterolemia, familial hypertriglyceridemia, and familial combined hyperlipidemia-appeared to represent dominant expression of three different autosomal genes, occurring in about 20% of survivors below 60 yr of age and 7% of all older survivors. Two other disorders-polygenic hypercholesterolemia and sporadic hypertriglyceridemia-each affected about 6% of survivors in both age groups. The most common genetic form of hyperlipidemia identified in this study has hitherto been poorly defined and has been designated as familial combined hyperlipidemia. Affected family members characteristically had elevated levels of both cholesterol and triglyceride. However, increased cholesterol or increased triglyceride levels alone were also frequently observed. The combined disorder was shown to be genetically distinct from familial hypercholesterolemia and familial hypertriglyceridemia for the following reasons: (a) the distribution pattern of cholesterol and triglyceride levels in relatives of probands was unique; (b) children of individuals with combined hyperlipidemia did not express hypercholesterolemia in contrast to the finding of hypercholesterolemic children from families with familial hypercholesterolemia; and (c) analysis of informative matings suggested that the different lipid phenotypes owed their origin to variable expression of a single autosomal dominant gene and not to segregation of two separate genes, such as one elevating the level of cholesterol and the other elevating the level of triglyceride. Heterozygosity for one of the three lipid-elevating genes identified in this study may have a frequency in the general population of about 1%, constituting a major problem in early diagnosis and preventive therapy.

/pdf/hyperlipidemia-in-coronary-heart-disease-ii-genetic-analysis-2t6bw6yk1z.pdf

Hyperlipidemia in Coronary Heart Disease II. GENETIC ANALYSIS OF LIPID LEVELS IN 176 FAMILIES AND DELINEATION OF A NEW INHERITED DISORDER, COMBINED HYPERLIPIDEMIA

-History of Human Genetics -The Human Genome: Chromosomes -The Human Genome: Genes and DNA -Formal Genetics of Humans: Linkage Analysis and Gene Clusters -Formal Genetics of Humans: Multifactorial Inheritance and Common Disease -Gene Action: Genetic Diseases - Gene Action: Developmental Genetics -Mutation: Spontaneous Mutation in Germ Cells -Mutation: Somatic Mutation, Cancer, and Aging -Mutation: Induction by Ionizing Radiation and Chemicals Population Genetics: Description and Dynamics -Population Genetics: Consanguinity, Genetics Drift -Human Evolution -Behavioral Genetics: Research Strategies and Examples -Behavioral Genetics: Affective Disorders and Schizophrenia -Behavioral Genetics: Differences Between Poulations -Genetic Counseling and Prenatal Diagnosis -Genetic Manipulations and the Biological Future of the Human Species

Human Genetics: Problems and Approaches

Werner’s Syndrome: A Review of its Symptomatology, Natural History, Pathologic Features, Genetics and Relationship to the Natural Aging Process

Plasma cholesterol and triglyceride levels were measured after an overnight fast in 500 consecutively studied 3-mo survivors of myocardial infarction. Virtually all patients under 60 yr of age (95% ascertainment) and a randomly chosen group of older survivors admitted to 13 Seattle hospitals during an 11 mo period were included. A comparison of their lipid values with those of 950 controls demonstrated that 31% had hyperlipidemia. These lipid abnormalities were most commonly found in males under 40 yr of age (60% frequency) and in females under 50 yr of age (60% frequency). Elevation in triglyceride levels with (7.8%) or without (15.6%) an associated elevation in cholesterol levels was three times more common in survivors than a high cholesterol level alone (7.6%). These results raise the possibility that hypertriglyceridemia may be as an important a risk factor for coronary atherosclerosis as hypercholesterolemia. The identification of hyperlipidemic survivors of myocardial infarction provided a unique source of probands for family studies designed to disclose the genetic origin of hyperlipidemia in coronary heart disease.

/pdf/hyperlipidemia-in-coronary-heart-disease-i-lipid-levels-in-2sn6dxl83j.pdf

Arno G. Motulsky

Papers

A quantitative assessment of plasma homocysteine as a risk factor for vascular disease. Probable benefits of increasing folic acid intakes

Hyperlipidemia in Coronary Heart Disease II. GENETIC ANALYSIS OF LIPID LEVELS IN 176 FAMILIES AND DELINEATION OF A NEW INHERITED DISORDER, COMBINED HYPERLIPIDEMIA

Human Genetics: Problems and Approaches

Werner’s Syndrome: A Review of its Symptomatology, Natural History, Pathologic Features, Genetics and Relationship to the Natural Aging Process

Hyperlipidemia in coronary heart disease. I. Lipid levels in 500 survivors of myocardial infarction