The clinical syndrome of chronic heart failure (CHF) is the hallmark of progressive cardiac decompensation, one of the most common chronic medical conditions that affect around 2% of the adult population worldwide irrespective of ethnic and geographic origin (Anonymous). Apart from ischemic heart disease, hypertension, infection, and inflammation, several other etiologic factors account for irreparable and irreversible myocardial damage leading to heart failure (HF). Genetic and genomic factors are now increasingly identified as one of the leading underlying factors (Arab and Liu 2005). These factors may be related to pathogenic alterations (mutation or polymorphism) within specific cardiac genes, mutations in genes incorporating single or multiple molecular pathways (protein families) relevant to cardiac structure and/or function, genetic or genomic polymorphisms of uncertain significance (gene variants, single-nucleotide polymorphisms (SNPs), and copy number variations (CNVs)), and epigenetic or epigenomic changes that influence cardiac gene functions scattered across the human genome. Recent genetic and genomic studies in both systolic and diastolic ventricular dysfunction, the hallmark of CHF, have revealed a number of mutations in genes belonging to specific cardiac protein families. For example, around 200 mutations are now known to exist in around 15 genes coding for several different types of sarcomere proteins (Liew and Dzau 2004). The sarcomere protein family, alone, accounts for the bulk of inherited cardiomyopathies including hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), restrictive cardiomyopathy (RCM), and left ventricular (LV) non-compaction (LVNC). In addition, there are several other potentially relevant factors involving different genes and genome-level elements. This article presents a systematic account on the available factual information and interpretations based on genetic and genomic studies in CHF (Liew and Dzau 2004). Genomic and molecular approaches have opened the way for a renewed debate for taxonomy of CHF (Ashrafian and Watkins 2007). The review draws attention to the potential diagnostic and therapeutic implications of genomic and transcriptional profiling in HF and translational genomics research that is likely to permit greater personalization of prevention and treatment strategies to address
Author Archives: Dhavendra Kumar
Genomics and Health in the Developing World
Genomics and Health in the Developing World provides detailed and comprehensive coverage of population structures, human genomics, and genome variation – with particular emphasis on medical and health issues – in the emerging economies and countries of the developing world. With sections dedicated to fundamentals of genetics and genomics, epidemiology of human disease, biomarkers, comparative genomics, developments in translational genomic medicine, current and future health strategies related to genetic disease, and pertinent legislative and social factors, this volume highlights the importance of utilizing genetics/genomics knowledge to promote and achieve optimal health in the developing world. Grouped by geographic region, the chapters in this volume address:
- Inherited disorders in the developing world, including a thorough look at genetic disorders in minority groups of every continent
- The progress of diagnostic laboratory genetic testing, prenatal screening, and genetic counseling worldwide
- Rising ethical and legal concerns of medical genetics in the developing world
- Social, cultural, and religious issues related to genetic diseases across continents
Both timely and vastly informative, this book is a unique and comprehensive resource for genetists, clinicians, and public health professionals interested in the social, ethical, economic, and legal matters associated with medical genetics
Oxford Specialist Handbook: Inherited Cardiac Disease
Many heart conditions are inherited and if not diagnosed and managed appropriately place the patient at risk of blackouts, weakening of the heart, or sudden death.While individually uncommon, inherited diseases of the cardiovascular system collectively represent a major health burden. Current recommendations suggest that individuals and families affected by inherited cardiovascular diseases should have access to specialist care in the form of multidisciplinary teams, with particular knowledge and experience in the diagnosis and management of these conditions. As a result, multidisciplinary services for inherited cardiovascular diseases, involving cardiologists, clinical geneticists, specialist nurses and genetic counsellors, are being developed throughout Europe.
Inherited Cardiac Disease provides healthcare specialists involved in the diagnosis and treatment of inherited cardiovascular disorders with a clinically relevant summary of genetic diseases and readily accessible information that can be used in everyday practice. Containing summaries of most common inherited cardiovascular disorders and describing cardiomyopathies, inherited arrhythmia syndromes, and other inherited cardiovascular syndromes with a focus on aetiology, presentation and management, it also provides the non-specialist with a detailed knowledge of inherited cardiovascular diseases, from the fundamentals of molecular biology and genetic testing to the detailed clinical information relevant to patient management.
Principles and Practice of Clinical Cardiovascular Genetics
Consisting of contributions from experts in all specialties of cardiovascular genetics and applied clinical cardiology, Principles and Practice of Clinical Cardiovascular Genetics serves as the comprehensive volume for any clinician or resident in cardiology and genetics. Each chapter provides a detailed and comprehensive account on the molecular genetics and clinical practice related to specific disorders or groups of disorders, including Marfan syndrome, thoracic and abdominal aortic aneurysms, hypertrophic, dilated and restrictive cardiomyopathies and Arrhythmogenic right ventricular cardiomyopathy, as well as many others. All sections comprehensively address cardiovasuclar genetic disorders, beginning with an introduction and including separate sections on the disease’s basic biological aspects, specific genetic mechanisms or issues, clinical aspects, genetic management (e.g., genetic diagnosis, risk assessment, genetic counseling, genetic testing), and clinical management issues. The final section exclusively addresses the management of cardiovascular genetic disorders, specifically considering stem cell therapy, genetic counseling, pharmacogenomics and the social and ethical issues surrounding disease treatment.
Genomics and Clinical Medicine
An important milestone in medicine has been the recent completion of the Human Genome Project. The identification of 30,000 genes and their regulatory proteins provides the framework for understanding the metabolic basis of disease. This advance has also laid the foundation for a broad range of genomic tools that have opened the way for targeted genetic testing in a number of medical disorders. This book is designed to be the first major text to discuss genomics-based advances in disease susceptibility, diagnosis, prognostication, and prediction of treatment outcomes in various areas of medicine. After building a strong underpinning in the basic concepts of genomics, the authors of this book, all leaders in the field, proceed to discuss a wide range of clinical areas and the applications now afforded by genomic analysis.
Genetic Disorders of the Indian Subcontinent
The Indian subcontinent is a vast land mass inhabited by over one billion people. Its rich and varied history is reflected by its numerous racial and ethnic groups and its distinct religious, cultural and social characteristics. Like many developing countries in Asia, it is passing through both demographic and epidemiological transitions whereby, at least in some parts, the diseases of severe poverty are being replaced by those of Westemisation; obesity, diabetes, and heart disease, for example. Indeed, as we move into the new millennium India has become a land of opposites; on the one hand there is still extensive poverty yet, on the other hand, some of the most remarkable developments in commerce and technology in Asia are taking place, notably in the fields of information technology and biotechnology. India has always fascinated human geneticists and a considerable amount of work has been done towards tracing the origins of its different ethnic groups. In the current excitement generated by the human genome project and the molecular and genetic approach to the study of human disease, there is little doubt that this field will develop and flourish in India in the future. Although so far there are limited data about genetic diseases in India, enough is known already to suggest that this will be an extremely fruitful area of
Inaugural Editorial “Cardiovascular Genetics and Genomics”
‘Applied and translational genetic and genomic practice of the cardiovascular medicine and surgery’
Professor Dhavendra Kumar, MD FRCP FACMG, Consultant in Clinical Genetics/ Cardiovascular Genetics, University Hospital of Wales, Cardiff, UK & Genomic Policy Unit, Faculty of Life Sciences and Education, The University of South Wales, UK
Most biologists and life sciences professionals would agree that we are now passing through the most active phase of the science of genetics. Even before we began sequencing the human and other genomes, genetics had established in a number of areas, particularly medicine and health. Since the discovery of chromosomes and universal acceptance of the principles of Mendelian and complex genetics, the practice of clinical medicine and public health went through major changes leading to acceptance of medical (clinical) genetics and diagnostic laboratory genetics as the integral component of any tertiary medical establishment. In addition, teaching and research in medical (clinical) genetics was incorporated to ensure evidence-based approaches to medical and health applications of genetics. Most specialist medical and healthcare providers acknowledged the importance of applied and translational genetics in respective specialist practices, notably in pediatrics, neurology, ophthalmology, oncology and lately in cardiology. This is evident from a number of books, monographs and journals dedicated to many specialist clinical and applied biology fields.
Since the completion of the human genome project and sequencing of the human genome, the focus rapidly shifted from genetics alone to wider field of genomics. With major rapid advances in genomic technologies (array comparative genomic hybridization, next generation sequencing (NGS) multi-gene diagnostic panels, whole exome sequencing and whole genome sequencing) it is now possible to look at the genome level for explanation(s) in a number of clinical situations empowering the clinician for making precise diagnosis and managing the condition in a more comprehensive manner. Cardiologists worldwide are now aware of the power of genetic and genomic diagnosis in dealing with wide ranging clinical cardiovascular conditions, particularly inherited or familial nature. The impact of this recent specialist discipline is evident in critical areas of clinical cardiology in dealing with acute events including sudden cardiac (arrhythmic) death syndrome, particularly the increasing utility of targeted multi-gene NGS panels in clinical and pathology (for example molecular autopsy) services.
The incorporation of applied and translational genetics and genomics in clinical practice and wider healthcare is expected to contribute in dealing with many new challenges that face the medical and health professions. This is evident from extended life expectancy leading to an unprecedented growth in the aging population, with the accompanying rising burden of aging-associated cardiovascular disorders. We have now enormous data and much improved understanding on how genomic variation may predispose to common or complex forms of cardiovascular diseases (coronary artery disease, hypertension, chronic heart failure, atrial fibrillation) in the community.
Delineation of the many rare genetic inherited cardiovascular conditions (ICCs) and identification of specific disease causing gene mutations and variants provide unique pathogenic insights into these diseases. The sequential steps in the molecular origins of cardiovascular syndromes are beginning to unfold, revealing the stunning complexities involved in the molecular bases of disease. We are beginning to understand how genetic and genomic factors interact with environmental or life-style factors over an entire lifetime to pattern and remodel function at the molecular, cellular, tissue, and organ levels and to ultimately manifest as subclinical or clinical cardiovascular disease. Many clinicians practicing cardiovascular medicine and surgery now accept the clinical importance of the molecular phenotyping of cardiovascular diseases, however, recognizing that the clinical phenotyping would remain mandatory. In addition, completely new phenotyping tools, such as molecular imaging and chemical profiling of patient-derived cells, are on the horizon.
Over the last 20 years, the field of clinical cardiovascular genetics and genomics has now established as reflected in specialist units in major tertiary healthcare institutions. There are now books and dedicated new bio-medical journals available focused on cardiovascular genetics encompassing specific issues related to wide ranging inherited cardiovascular conditions. ‘Cardiovascular Genetics and Genomics’ is a new open-access journal publishing original research, meta analyses, reviews, case commentaries and updates on recent developments focusing on genetic and genomic aspects of wide range of cardiovascular conditions. The journal particularly focuses on delineation of the clinical phenotypes, new genes and variants, genotype-phenotype correlations, basic and clinically applied molecular genetics, next generation sequencing and new therapeutic developments (drugs & devices). The original cardiovascular research will highlight the omics family- proteomics, metabolomics, functional genomics and systems biology – as well as clinical trials in the burgeoning field of pharmacogenomics related to cardiovascular medicine. The journal also features current and comprehensive reviews in the areas of recent advances in cardiovascular development, Mendelian cardiovascular conditions, new diagnostic and therapeutic progress, and controversies in cardiovascular genetics. A dedicated news section summarizes the new developments in the field, highlighting articles likely to impact the management of cardiovascular disorders. Other features include clinical case reports and studies, book reviews, and letters to the editor.
The following categories (not limited) of research papers and articles are published in Cardiovascular Genetics & Genomics:
- Cardiovascular development
- Congenital heart disease
- Inherited cardiomyopathy-Hypertrophic cardiomyopathy (HCM), Dilated cardiomyopathy, Arryhthmogenic right ventricular cardiomyopathy (ARVC)
- Cardiovascular genes- Sarcomere, cytoskeletal, junctional, ion channel and others
- Inherited arrhythmia- Long QT Syndrome (LQTS); Short QT Syndrome, Brugada syndrome, Catecholaminergic polymorphic ventricular tachycardia (CPVT)
- Inherited vascular/ connective diseases: Marfan syndrome, Loeys-Dietz syndrome, Ehlers-Danlos syndrome and other connective tissue diseases with cardiovascular phenotypes
- Hypertension- systemic and pulmonary arterial
- Inherited metabolic disease with cardiovascular phenotypes
- Sudden unexplained/cardiac death (infant and adult)
- Inherited neuromuscular disorders with cardiovascular phenotypes
- Complex cardiovascular disease (coronary artery disease; hypertension)
- Molecular cardiology- diagnostic, experimental, applied and translational
- Cardiovascular pharmacogenetics & pharmacogenomics
- Bio-banking and cardiovascular genomics databases
- Gene, Stem cell and somatic cell therapy in cardiovascular diseases
- Surgical and non-invasive therapy for inherited cardiovascular conditions
- Education and training in cardiovascular genetics and genomics
- Ethical, legal, social issues related to cardiovascular genetics and genomics
All manuscripts are submitted on line and should follow the usual format and include: the title, authors, institute affiliations, name/address of the corresponding author, selection of search engine key words (not more than 10), name/ address of relevant ethical approval authority, declaration on conflict of interest, statement on commercial/ financial benefits and copyright authorization for any illustrations, tables or part of the text included in the manuscript. References should be cited in the text with author and year; use suffix et al for more than 2 authors in the reference cited. All references should be listed in alphabetical order. Name of the soft ware reference manager should be indicated in the manuscript.
As per journal policy, all manuscripts are independently peer-reviewed and final decision is made by the editor in chief reflecting views of the lead- editor (usually a member of the editorial board or a guest editor) and external reviewers. All accepted manuscripts are published (online and print) subject to copyright agreement with the publishers (see below). The journal is open-access and a charge is applicable. The tariff is available on request and specific charge will be advised on acceptance of the manuscript. However, the open access charge could be waived in exceptional circumstances, for example an invited review or commentary authorized by the editor in chief. The open access charge may also be waived or discounted on voluntary and for an individual publication. All paid or waived open-access publications would be made available to all registered readers. Any reader may access the paper or article subject to a small downloading fee advised at the time of consumer registration.
The time required for moving research findings from “bench to bedside” is decreasing exponentially with the growth of applied and translational genomic studies inspired by large number of studies worldwide. All these developments and efforts are welcome and society has huge expectations, particularly the personalized healthcare. Based on past experiences in clinical genetics, new genetic and genomic advances invariably raise societal and professional concerns on wide ranging ethical, legal, and social issues that must be confronted by the cardiology community together with patients, ethicists, and lawyers. The costs of personalized medicine, including refined diagnosis and personalized therapies, would be required to match with anticipated improved outcomes. It is important to remember that the ultimate delivery of personalized health care rests on the shoulders of the clinicians who interface directly with patients.
Conflict of Interest-
‘Cardiovascular Genetics and Genomics’ is published by The Genomic Medicine Foundation (UK) Ltd, a not-for-profit company registered in England and Wales (Registered Number 8749919). The publisher holds all legal rights and acquires all financial or any other benefits of any published material in the journal. The reader may refer to www.genomicmedicine.org for further information on the Foundation and the new Journal.
Global Alliance for Genomics and Health
The Global Alliance for Genomics and Health (Global Alliance) was formed to help accelerate the potential of genomic medicine to advance human health. It brings together over 220 leading institutions working in healthcare, research, disease advocacy, life science, and information technology. The partners in the Global Alliance are working together to create a common framework of harmonized approaches to enable the responsible, voluntary, and secure sharing of genomic and clinical data.
The Global Alliance for Genomics and Health (Global Alliance) is an international coalition, dedicated to improving human health by maximizing the potential of genomic medicine through effective and responsible data sharing. The promise of genomic data to revolutionize biology and medicine depends critically on our ability to make comparisons across millions of human genome sequences, but this requires coordination across organizations, methods, diseases, and even countries. The members of the Global Alliance for Genomics and Health are working together to create interoperable approaches and catalyze initiatives that will help unlock the great potential of genomic data.
Since its formation in 2013, the Global Alliance for Genomics and Health is leading the way to enable genomic and clinical data sharing. The Alliance’s Working Groups are producing high-impact deliverables to ensure such responsible sharing is possible, such as developing a Framework for Data Sharing to guide governance and research and a Genomics API to allow for the interoperable exchange of data. The Working Groups are also catalyzing key collaborative projects that aim to share real-world data, such as Matchmaker Exchange, Beacon Project, and BRCA Challenge.
For further information visit www.genomicsandhealth.org
Genomic Medicine – Prospects, Promises and Expectations
Dhavendra Kumar, Institute of Cancer & genetics, University Hospital of Wales, Cardiff, UK; Genomic Policy Unit, The University Hospital of Wales, Pontypridd, UK and The Genomic Medicine Foundation (UK).
The natural selection theory for evolution put forward by Charles Darwin had clear overtones reflected in some of our present-day concepts of the genetic basis of biological life. Mendel’s laws of inheritance, and successive discoveries in various aspects of genetics, laid the foundation of Mendelian genetics, a major recognized field within the science of genetics. This subsequently became the cornerstone for human genetics. Several years later the science of genetics is rewarded with the genome era. The future now appears bright, opening up many opportunities on the horizon. Clinical genetics is now a recognized medical specialty among several disciplines comprising the current spectrum of modern medicine. The basis of clinical genetics is grounded in the sound knowledge and understanding of medical genetics which emerged as a spin-off of ‘Human Genetics’.
Fifty years after the discovery of the double-helix structure of the deoxyribonucleic acid [DNA] molecule (Watson and Crick, 1953), characterization of the complete sequence and organization of the human genome was successfully accomplished (Lander et al., 2001; Venter et al., 2001). This major scientific achievement laid the foundation of ‘human genomics’; that section of the biological sciences which studies variations, mutations and functions of genes and controlling regions, and their implications on human variation, health and disease. This is strengthened by developments in the other areas of genomics relating to bacteria, vectors, parasites, animals and plants.
The identification of all human genes and their regulatory regions provides the essential framework in our understanding of the molecular basis of disease. This advance has also provided a firm foundation for the future development of genomic technologies that can be applied to modern medical science. Rapid developments in global gene analysis, gene product analysis, medical bio-informatics, and targeted molecular genetic testing are destined to change the practice of modern medicine (Guttmacher and Collins, 2002). However, many practicing clinicians perceive developments in genomics as primarily confined to the research arena with little clinical applicability. DNA/RNA-based methods of disease susceptibility screening, molecular-based disease diagnosis and prognosis, and genomics-based therapeutic choices and prediction of treatment outcome are some of the key promising areas that have influenced and raised expectations for reforming the practice of modern clinical medicine.
Undoubtedly the science of genomics holds tremendous potential for improving human health. The expert working group convened by the World Health Organization [WHO] has made several recommendations on the scope and application of genomics on global health (WHO, 2002). It is acknowledged that the information generated by genomics will provide major benefits in the prevention, diagnosis and management of communicable and genetic diseases as well as other common medical diseases, including cardiovascular diseases, cancer, diabetes and mental illnesses (Cardon and Bell, 2001). Together these constitute the major health burden, as reflected in chronic ill-health and mortality. In addition, a number of infectious diseases are associated with genomic mutations manifesting in the form of increased susceptibility, clinical severity, desired therapeutic response to anti-microbial therapy and in conferring protection. It is possible that the protective effect of a microbial vaccine might be influenced by genomic variation.
The sequence of the entire human genome is nearly complete but this is not limited to one individual alone . Each person carries a distinct sequence. The variation among all humans is reflected in variation within the human genome. The genomic variation between individuals together with environmental factors probably determines the disease susceptibility, and is important in drug efficacy and side effects (Holden, 2000; Chakravati, 2000). The key to genomic variation lies in finding single nucleotide polymorphisms [SNPs] and its use in disease association studies (Stephens et al. 2001). The positional cloning (identifying the gene by location followed by functional analysis) of the disease susceptibility loci will depend upon the successful application of haplotype associations. In addition, these will be important in clinical studies to find individuals in whom a drug is likely to be efficacious. The use of SNPs in pharmacogenetics is currently restricted to studying genes for drug-metabolizing enzymes, such as P450s, and variations in genes that target drug receptors. The newly emerging dynamic field of pharmacogenomics is an exciting application of genomic variation in drug discovery and drug development.
The recent cloning of real disease susceptibility genes for multifactorial diseases is encouraging, for example, the identification of NOD2 as a susceptibility gene for Crohn’s disease (Hugot et al., 2001 and Ogura et al., 2001). This is a major development in understanding the pathophysiology of inflammatory bowel disease. Similar studies are likely to unravel the genetic mechanisms in other complex medical diseases. A comprehensive SNP map will allow the cloning of other susceptibility alleles. However, this will depend upon population sample and size, the method employed, linkage disequilibrium or association studies rather than the technology used (Cardon and Bell, 2001). Some of the best genetic studies of this kind include susceptibility to infectious disease, for example an association between chemokine receptors (CCR5) and HIV susceptibility, and between the bacterial transporter protein Nramp and resistance to macrophage-infecting bacteria such as Mycobacterium tuberculosis. Similarly, various alleles at the G6PDH locus determine malaria susceptibility (Tishkoff et al., 2001).
These kind of studies and clinical applications of the resulting outcomes are not without ethical concerns. Some of the questions and concerns are related to ownership of the genes and freedom to use collected DNA for such studies. These are complex and emotional issues, especially when dealing with populations who may have been exploited. These issues should always be dealt with carefully under the statutory requirements and rules.
There has been a tremendous surge in various sub-specialties and technologies with names ending in -omics. We are rapidly moving into the “omics” era. In addition to genomics, several new specialist fields with an ‘omics’ suffix have recently appeared, for example, pharmacogenomics, nutrigenomics, metabonomics, transcriptomics, proteomics, micribiomics, glycomics, toxicogenomics, and many more. Whatever the basis of distinction might be, the driver of all these terms is GENOMICS – the study of genomes in its entirety.
Genomics is not just about genome sequencing. Apart from full-length cDNAs and their sequences, copies of mRNAs that actually exist and code for different proteins are probably more important. The study of proteins thus derived falls within the broad field of proteomics, a likely outcome of functional genomics and probably a true companion to genomics. It is likely that eventually proteomics will have more practical applications in clinical medicine. This is rapidly moving ahead with the completion of the HapMap project (Nature, 2005) and the future ‘functional-variant database’, a natural outcome of the HapMap project (Gibbs, 2005).
It is vital that existing gaps in our knowledge about various ‘omics’ disciplines are filled to ensure efficient use of the valuable information emerging from research. It is also important that the gap between ‘genetic professionals’ and the ‘primary-care community, and as well as the ‘public health community’, is narrowed (Khoury et al., 2003). Integration of this knowledge in the medical education curriculum and the continued professional education programs is urgently required to ensure applications of genomics in the provision of healthcare.
During the last two decades, the practice of medical genetics or clinical genetics, has found its niche within the broad horizon of clinical medicine. Genetic services now constitute a small, but albeit important, component of modern medical practice and public health. Currently, genetic services focus on providing information on chromosomal and single-gene diseases with limited contribution to multifactorial/polygenic diseases. How would this then be different from genomics? Already there is tremendous enthusiasm for the recently introduced term of ‘genomic medicine’. In a primer on genomic medicine, Guttmacher and Collins (2002) viewed “genetics as the study of single genes and their effects” and genomics as “the study not just of single genes, but of the functions and interactions of all the genes in the genome.” In simple terms, there is a quantitative difference between the two fields – the study of multiple genes as opposed to one gene. Thus genetics can be seen as part of genomics! However, there is a qualitative difference between genetics and genomics in medical and health applications ranging from the concept of disease in genetics to the concept of information in genomics (Khoury et al., 2003).
The practice of medical genetics has traditionally focused on those conditions that result from specific alterations or mutations in single genes (e.g., inborn errors of metabolism, Duchenne muscular dystrophy, and Huntington’s disease), whole or part of chromosomes (e.g., trisomy 21 in Down syndrome), or associated with congenital malformations and developmental disabilities. The existing model of medical genetic services for these conditions includes laboratory diagnosis, genetic counseling and management. This is supported by public health measures to ensure delivery of genetic services and genetic screening (e.g., new-born screening or screening the high-risk population). On the other hand, the practice of genomics in medicine and public health will focus on information resulting from variation at one or multiple loci and strong interactions with environmental factors, for example diet, drugs, infectious agents, chemicals, physical agents, and behavioral factors (Khoury et al., 2003).
What medical and public health applications could one foresee following the completion of human genome sequence in 2003? How could these be applied and delivered to the 95% of human diseases that do not fall under the rubric of genetic disorders? These are some of the likely questions related to genomic medicine. Medical and public health professionals urgently need to make the changes necessary to accommodate rapid identification and characterization of the numerous genomic variants at multiple loci which increase or decrease the risks for various diseases, singly or in combination with other genes, and with various chemical, physical, infectious, pharmacologic, and social factors (Khoury, 1999). This genetic and genomic information is crucial in assessing the disease susceptibility among healthy individuals, and in personalized primary and secondary prevention planning. Collins and McKusick (2001) stated that “By the year 2010, it is expected that predictive genetic tests will be available for as many as a dozen common conditions, allowing individuals who wish to know this information to learn their risks for which interventions are or will be available. Such interventions could take the form of medical surveillance, lifestyle modifications, diet, or drug therapy. Identification of persons at highest risk for colon cancer, for example, could lead to targeted efforts to provide colonoscopic screening to those individuals, with likelihood of preventing many premature deaths.”
Personalized medicine will encompass not only common medical diseases, but could include a wide range of preventable diseases [www.genovations.com ]. Genetic testing for future disease susceptibility using multiple genomic variants will be possible and affordable with the application of ‘high throughput’ microarrays-based genetic testing.
A wealth of information on genomics is rapidly being acquired with the potential for major impact on human health. However, this data and information is scattered throughout several scientific journals, reviews and state-sponsored reports and bulletins. A clinician or health professional often has difficulty in accessing and assimilating this information for application in the medical and public health practice. More importantly, an inability to assimilate and interpret leads to frustration and avoidance of potentially useful information. This article sets out the subject from the historical progress to general aspects of genomics and the describing in some detail the medical and health applications.
Exciting new developments in biotechnology and bioinformatics have opened unimaginable horizons that were inconceivable only few years ago. The talk of the next generation sequencing (NGS) is not restricted to the bench of few interested post-doctoral level and young investigators. It is evident everywhere and is now firmly engrained in minds and souls of genetic and genomic researchers, clinicians and health professionals. A number of genetic diseases or group of rare disorders can now be investigated with confidence using multi-gene NGS panels reducing the time in making an accurate diagnosis and helping the clinician to plan focussed clinical investigations and management. Further, many undiagnosed or poorly defined conditions and complex clinical cases can now be investigated using powerful genome technologies, notably the comparative array genomic hybridisation (array CGH), whole exome sequencing (WES) and even whole genome sequencing (WGS), albeit with limited outcomes (Berg et al., 2011; Biesecker and Green, 2014). The focus has shifted from finding the pathogenic sequence variations to functional importance of genome level changes. Unravelling of the complexities of the RNA molecules has made a huge impact in molecular and experimental biology, the basis for transcriptomics (Xa et al., 2014). In addition, challenging and controversial stem cell genomic research has captured the headlines with promises and expectations of massive proportions, notably for neurodegenerative disorders (Lindvall, 2004). Targeting specific segments of the gene using the oligonucleotide skipping technique has raised expectations for treating a number of Mendelian genetic conditions (Goodchild, 2011). This is truly the beginning of the promising phase for applied and translational genomics.
The enormous genomic data and information generated by genome wide association studies (GWAS), deciphering the complex phenotypes by copy number variations and single nucleotide polymorphisms and applying knowledge gained from genetic and genomic analysis in rare Mendelian disorders have offered fine molecular understanding of the underlying pathogenic mechanisms. There is lot of enthusiasm for applying next generation sequencing methods (alongside the Sanger sequencing) in new gene discoveries, unravelling novel molecular mechanisms and identifying critical focal points in molecular pathways in designing and developing targeted molecular therapy models.
Several major global initiatives are being pursued to curate and annotate enormous genomic data and information from new genomic technological advances. The common theme is genotype-phenotype correlation. Leaders in this approach include the Human Variome Project (www.humanvariomeproject.org), Gen2Phen project (www.gen2phen.org) and recently launched Human Phenome Project (Freimer and Sabbati, 2003). Successful outcomes of these projects might offer clarification and evidence that could be applied in medicine and health. However, there is sufficient evidence around supporting the argument for genomic applications for enhancing the diagnostic and probably the prognostic potential of genomic medicine and health. Promising new therapeutic developments have followed, particularly discovery and development of new drugs and pharmacogenetic / pharmacogenomics evidence necessary for personalised pharmacotherapy.
So how do genomics and all related genome technologies impact upon Medicine and Health? Do we have enough data, understanding and robust evidence to apply and translate in practising effective and efficient clinical medicine? We are probably safe to gently move in the next phase of the genomic and personalized medicine. Has genome sequencing done any good to human health? Francis Collins believes that ‘I think there are people who’s lives have been saved because of the study of the genome.’
Genomic medicine and health genomics is a global phenomenon. Prospects of this major revolution are enormous and unimaginable. Skeptics argue that this is all disproportionately overhyped. Nevertheless massive investments in all parameters are poured into this field globally with sky-high promises and huge expectations. A major global alliance has committed itself to bring all geneticists, genome scientists, genome technology experts, genetic clinicians and health genomic experts together for the benefit of global health (www.genomeandhealth.org)
Perhaps, it is most relevant at this juncture to remind us that the practice of Medicine is an art based on sound scientific principles. It would be appropriate to quote Sir William Osler’s remarks, “If there were no individual variability, medicine would have been science not an art.” Genomics in this context provides the basis of individual variability and the modern genomic era clinician will need to ensure that this continues to be applied as an art.
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Genomic Medicine – Principles and Practice
The first edition of Genomics and Clinical Medicine provided an overview of genomics-based advances in disease susceptibility, diagnosis, and prediction of treatment outcomes in various areas of medicine. Since its publication, the science of genomics has made tremendous progress, and exciting new developments in biotechnology and bioinformatics have created possibilities that were inconceivable only a few years ago. This completely revised second edition of Genomic Medicine reflects the rapidly changing face of applied and translational genomics in the medical and health context and provides a comprehensive coverage of principles of genetics and genomics relevant to the practice of medicine. The first section lays foundation to the practice of genomic medicine. New chapters in this section include bioinformatics, proteomics, microbial genomics and genomic education. Detailed discussions of genetic/genomic testing and screening and the ethical, legal, and social issues (ELSI) crucially address genethics and genomethics in the practice of Genomic Medicine. The second section includes clinical practice oriented chapters highlighting genomic applications (array comparative genomic hybridization, exome genome sequencing and new generation generation sequencing) in clinical diagnosis of congenital developmental malformations, Mendelian genetic disorders, and complex cardiovascular, neuro-psychiatric, ophthalmic, dermatologic, inflammatory and pediatric disorders. Separate chapters discuss microbial genomics with emphasis on the role of genomics in targeted antimicrobial therapy and development of genomic class of new vaccines. New developments in gene/ cell-based somatic therapy, regenerative medicine and targeted molecular therapy are discussed in respective chapters. All chapters are thoroughly indexed and supported by a carefully compiled glossary relevant to genetic and genomic medicine.