Gregory R. Bock – författare

This book features scientists from a broad spectrum of disciplines discussing recent data on aggression in laboratory animals with particular reference to possible implications for understanding human aggression.  Chapters focus on the major current experimental issues in the study of aggression in humans and animals. The extensive discussions deal with specific problems of interpretation at the molecular level, as well as general issues relating to our understanding of human and animal aggression.

This book features scientists from a broad spectrum of disciplines discussing recent data on aggression in laboratory animals with particular reference to possible implications for understanding human aggression.  Chapters focus on the major current experimental issues in the study of aggression in humans and animals. The extensive discussions deal with specific problems of interpretation at the molecular level, as well as general issues relating to our understanding of human and animal aggression.

This book features contributions from experts in cell biology, genetics, neurobiology, immunology and structural biology.  The unifying element is that they all study processes of cell shape change and motility.  Several key questions in this field of research are discussed: What are the organising principles behind cell shape change? Are there ‘master switches’ present in every cell type? How are extracellular signals interpreted by the cell in order to activate intracellular mechanisms? What is the influence of the extracellular matrix on cell movement and internal signalling pathways? How do pathogens subvert cellular systems in order to stimulate or block their uptake?

The book addresses all of these important questions.  Data are presented on the key proteins that regulate cell shape: the GTP binding proteins of the Rho family. There are also extensive discussions of the potential applications of the data to clinical problems, particularly that of cell motility in cancer.

This title provides an extremely helpful analysis of genes that may be associated with autoimmunity, and answers questions such as how these genes can be identified, and how the functions of the gene products can be elucidated. Incorporating data on disease-associated chromosomal loci that has been accumulated from inbred mice, the title: descibes how some susceptibility loci may be common to many diseases, whereas others are relatively disease specificdiscusses the importance of developing criteria for establishing the significance of these different categories of disease-associated loci.

This title provides an extremely helpful analysis of genes that may be associated with autoimmunity, and answers questions such as how these genes can be identified, and how the functions of the gene products can be elucidated.

Incorporating data on disease-associated chromosomal loci that has been accumulated from inbred mice, the title:

descibes how some susceptibility loci may be common to many diseases, whereas others are relatively disease specific discusses the importance of developing criteria for establishing the significance of these different categories of disease-associated loci.

Cigarette smoking is estimated to lead to 4.9 million premature deaths per year worldwide. This is predicted to rise to 10 million by 2020. In western countries it kills half of all smokers who fail to stop. The prevailing model for tobacco addiction is that nicotine from cigarettes rewards smoking and punishes abstinence, tapping into a motivational system of operant conditioning that requires no conscious awareness. However, there are also accounts which involve cognitive biases and the effect of nicotine on impulse control. The brain pathways involved have been studied extensively, but the role of different nicotine receptor subtypes and other neurotransmitter systems is still subject to debate. In western countries, cigarette smoking as an adult has a heritability of 30-50% and candidate genes have been identified that may contribute in part to addiction susceptibility. Many socio-cultural correlates of cigarette smoking have been established, but a comprehensive model that accounts for these and links them with the psychobiological aspects of nicotine addiction has not been forthcoming. Structured behavioural support programmes aid cessation attempts, as do a number of pharmacotherapies, most notably nicotine replacement treatments and bupropion, but the underlying mechanisms are unclear. This book deals with the problems involved in understanding and treating nicotine and tobacco addiction. Topics covered include the nature of the worldwide health problem posed by cigarette smoking, the psychodynamics of cigarette addiction, and the basic pharmacology and biochemistry of nicotine and its effect on the brain. Further chapters analyse the genetic basis of susceptibility to nicotine addiction. Finally, the contributors address approaches to therapy. A continuing theme in the discussions throughout the book is how best to treat nicotine addiction, given that many smokers would like to stop smoking but are unable to do so because of their addiction. This book will be of great value to all psychologists and psychiatrists working on addiction, specifically to nicotine but also to other compounds and behaviours. It will also be of interest to neuroscientists and pharmacologists working on nicotine receptors and the brain pathways involved in dependence, as well as to biochemists, molecular biologist and to public health officials.

Heart failure is the main cause of death and disability in the industrialized world. There is a major need for novel therapeutics for prevention and reversal of cardiac pathology associated with heart failure and cardiac enlargement. Over recent years, dramatic progress has been made in unravelling the cellular circuitry involved in cardiac failure, as well as in normal cardiac growth, development and apoptosis. This work has revealed new and unexpected therapeutic targets in the heart. In addition, advances in understanding the role of stem cells in cardiac physiology have suggested strategies for cardiac repair and regeneration once thought impossible.

This book describes the work of leading investigators studying the basic mechanisms of cardiac growth, function and dysfunction. There are also exciting contributions from researchers developing novel therapeutic strategies for cardiac disease. The unique feature is the discussions amongst the contributors, which always return to the same basic problem: how can new data from biological studies be used to design novel therapies for the treatment of cardiac dysfunction following myocardial infarction, hypertension and other disorders?

With its strong emphasis on translational research, this book will appeal to both scientists and clinicians interested in diminishing the impact of the current epidemic of cardiac diseases.

Empathy is the process that allows us to share the feelings and emotions of others, in the absence of any direct emotional stimulation to the self. Humans can feel empathy for other people in a wide array of contexts: for basic emotions and sensation such as anger, fear, sadness, joy, pain and lust as well as for more complex emotions such as guilt, embarrassment and love. It has been proposed that, for most people, empathy is the process that prevents us doing harm to others.

Although empathy seems to be an automatic response of the brain to others’ emotional reactions, there are circumstances under which we do not share the same feeling as others.  Imagine, for example, that someone who does the same job as you is paid twice as much. In this case, that person might be very satisfied with their extra salary, but you would not share this satisfaction. This case illustrates the ubiquitous feeling of fairness and justice.

Our sense of fairness has also become the focus of modern economic theories. In contrast to the prominent self-interest hypothesis of classic economy assuming that all people are exclusively motivated by their self-interest, humans are also strongly motivated by other-regarding preferences such as the concern for fairness and reciprocity. The notion of fairness is not only crucial in personal interaction with others in the context of families, workplace or interactions with strangers, but also guides people’s behaviour in impersonal economic and political domains.

This book brings together work from a wide range of disciplines to explain processes underlying empathy and fairness. The expert contributors approach the topic of empathy and fairness from different viewpoints, namely those of social cognitive neuroscience, developmental psychology, evolutionary anthropology, economics and neuropathology. The result is an interdisciplinary and unitary framework focused on the neuronal, developmental, evolutionary and psychological basis of empathy and fairness. With its extensive discussions and the high calibre of the participants, this important new book is essential reading for anyone with an interest in this topic.

Dengue virus is a member of the Flaviviridae family, which includes viruses associated with human diseases such as yellow fever, Japanese encephalitis and hepatitis C. Dengue fever is transmitted by mosquitoes, principally Aedes aegypti. There are four serotypes of dengue virus, of which DENV-2 has been the most prevalent in many recent epidemics. Following primary infection, lifelong immunity develops, preventing repeated assault by the same serotype. However, the non-neutralizing antibodies from a previous infection or maternally acquired antibodies are thought to form complexes with a different serotype during a subsequent infection and cause dengue haemorrhagic fever/dengue shock syndrome, which can be fatal. There is no treatment or vaccine available today that can combat this emerging and uncontrolled disease.

This book features contributions from the world’s leading researchers working on dengue and related flaviviruses who examine the current state of the art in the molecular biology of the dengue virus. Particular emphasis is placed on the structure and function of the virus and the targeting of virus proteins by potential antiviral agents. The pathogenesis of dengue and dengue haemorrhagic fever are discussed in detail, especially the target cells and the specific receptors on these cells, thereby developing a clear overview of host and viral factors that contribute to dengue haemorrhagic fever. Finally, the book reviews the therapeutic options, paying particular attention to ways in which vector, host and environment can play a critical role in the spread of this disease.

With dengue fever and other emerging viral diseases becoming increasingly prevalent around the world, this book provides valuable insight into the virus that causes this disease and potential ways to manage it. It is essential reading for all those working in tropical diseases, public health and virology.

Praise from the reviews:

"The book provides an excellent summary of dengue/flavivirus research and is important for individuals and institutions interested in emerging infectious diseases." MICROBIOLOGY TODAY

This book explores existing and potential strategies for using the genome sequences of human, mouse, other vertebrates and human pathogens to solve key problems in the treatment of immunological diseases and chronic infections.  The assembled genome sequences now provide important opportunities for solving these problems, but a major bottleneck is the identification of key sequences and circuits controlling the relevant immune reactions. This will require innovative, interdisciplinary and collaborative strategies of a scale and complexity we are only now beginning to comprehend.

Specific problems addressed include the following:

What kinds of information are we lacking to understand how the genome sequence specifies the differentiation and response of immune system cells, and system behaviour such as immunological memory and tolerance? Which genome sequences and cellular circuits cause or prevent pathological immune responses to foreign pathogens, allergens or self-tissues? Which host and pathogen genome sequences and cellular circuits explain the failure of sterilizing immune responses to sophisticated human pathogens such as the agents of tuberculosis, malaria, metazoan parasites and chronic viruses?

Containing contributions from a range of leading experts in the field, this book provides an important new perspective for clinical immunologists and basic researchers alike.

The past decade has seen mounting global concern regarding viral outbreaks such as SARS, avian influenza and West Nile virus. In 2004 and 2005, reports of bird-to-human, and possible human-to-human, transmissions of the H5N1 influenza viruses raised fears that these viruses could cause a pandemic on the scale of the Spanish flu pandemic of 1918.   Previous to this, a novel coronavirus had been identified as the aetiological agent of the severe acute respiratory syndrome (SARS), a new respiratory viral disease that emerged at the end of 2002 and caused profound disturbances in over 30 countries worldwide in 2003. It is not known whether the SARS coronavirus will re-emerge, especially since its origins and potential reservoir(s) are unresolved. However, these outbreaks have shown that these viruses can emerge in any part of the world at any time. This book critically evaluates the latest scientific evidence on novel or re-emerging viral diseases and brings together contributions from world experts on this topic, explaining best practice in their area, and discussing lessons learned and how best to collaborate to prevent and control future outbreaks. Topics covered include: the latest advances in virology, particularly in the area of epidemiologydiagnosticsanimal models for viral infectionantiviral and vaccine developmentNovel and Re-emerging Respiratory Viral Diseases offers a comprehensive and interdisciplinary account of all aspects of the topic, from basic molecular biology to public health issues, and is therefore essential reading for virologists, infectious disease specialists, public health managers, researchers and epidemiologists, as well as those working in vaccine development, pharmaceutical medicine and drug discovery

The astounding diversity of the immune system and the complexity of its regulatory pathways makes immunology a combinatorial science. Computational analysis has therefore become an essential element of immunology research and this has led to the creation of the emerging field of immunoinformatics. This book is the first to feature thorough coverage of this new field.

Immunoinformatics facilitates the understanding of immune function by modelling the interactions among immunological components. Biological research provides ever deeper insights into the complexity of living organisms while computer science provides an effective means to store and analyse large volumes of complex data. Combining the two fields increases the efficiency of biological research and offers the potential for major advances in the study of biological systems.

This book encompasses key developments in immunoinformatics, including immunological databases, sequence analysis, structure modelling, mathematical modelling of the immune system, simulation of laboratory experiments, statistical support for immunological experimentation and immunogenomics.

The difficulties in effective application of bioinformatic tools in immunology arise at both ends of the spectrum: most immunologists have only a limited comprehension of sophisticated data analysis and applicability and limitations, while the average computer scientist lacks knowledge of the depth and complexity of biological data. The purpose of this book, therefore, is to present contributions from a multidisciplinary team of biologists and computer scientists to explore the issues related to better understanding of immune function and, in particular, to help apply new computer science methods to immunological research.

Related Novartis Foundation symposia:

247 In Silico Simulation of Biological ProcessesChair: Denis Noble

252 Generation and effector functions of regulatory lymphocytesChair: Jean-François Bach

Understanding stem cells at the molecular level is essential to understanding their behaviour in a physiological context. This volume in our acclaimed Novartis Foundation series features animated discussion from the world’s experts in this topic on the important ethical issues that are raised by research on stem cells. They review the various regulatory regimes, which apply in different countries – a key factor in determining where future stem cell research is carried out. Potential clinical applications covered in the book include the production of cardiomyocytes to replace damaged heart tissue, the production of insulin-producing cells for patients with diabetes, and the generation of neurons for the treatment of patients with Parkinson’s disease or spinal cord injury. Particular attention is paid to the factors that maintain stem cells in a pluripotent state or which drive them to create differentiated and lineage-committed cells in vitro and in vivo.  Nuclear reprogramming, the process by which a nucleus acquires developmental potential, is covered here as well. It is relevant to stem cell research generally, and also to research on the cloning of animals by nuclear transfer. This book is an essential purchase for all those engaged in stem cell research, whether in the laboratory, the clinic or the regulatory authorities.From the reviews:"...this book provides: a comprehensive overview of current issues in stem cell research, with contributions from leading figures..."—BRITISH SOCIETY OF CELL BIOLOGY

Understanding stem cells at the molecular level is essential to understanding their behaviour in a physiological context. This volume in our acclaimed Novartis Foundation series features animated discussion from the world’s experts in this topic on the important ethical issues that are raised by research on stem cells. They review the various regulatory regimes, which apply in different countries – a key factor in determining where future stem cell research is carried out.

Potential clinical applications covered in the book include the production of cardiomyocytes to replace damaged heart tissue, the production of insulin-producing cells for patients with diabetes, and the generation of neurons for the treatment of patients with Parkinson’s disease or spinal cord injury. Particular attention is paid to the factors that maintain stem cells in a pluripotent state or which drive them to create differentiated and lineage-committed cells in vitro and in vivo.  Nuclear reprogramming, the process by which a nucleus acquires developmental potential, is covered here as well. It is relevant to stem cell research generally, and also to research on the cloning of animals by nuclear transfer. 

This book is an essential purchase for all those engaged in stem cell research, whether in the laboratory, the clinic or the regulatory authorities.

From the reviews:

"...this book provides: a comprehensive overview of current issues in stem cell research, with contributions from leading figures..."—BRITISH SOCIETY OF CELL BIOLOGY

Retinal dystrophies are the major causes of incurable blindness in the Western world. Our insight into their aetiology has improved remarkably over the past decade and a number of key genes have been identified. Together with a more detailed understanding of disease processes, this knowledge is stimulating new approaches to therapeutic strategies involving gene therapy, growth factors and retinal cell transplantation. 

Molecular genetic studies have provided detailed information on the pathogenesis of retinal dystrophies. An important proof of principle that gene therapy holds great promise for the treatment of these conditions was demonstrated in the rds mouse: introduction of a functional copy of the peripherin gene subretinally resulted in complete rescue of rod outer segment structure. Novel approaches are being developed based on the manipulation of biochemical pathways that previously were not considered relevant to these diseases. For example, renewed interest in retinal dystrophy pathogenesis led to the successful use of high dose vitamin A treatment in Sorsby fundus dystrophy. 

This important new book covers all aspects of retinal dystrophies from the molecular and developmental biology of these disorders to possible therapeutic approaches, with special reference to gene therapy. Specific chapters deal with the molecular genetics of gene therapies, clinical genetic studies, molecular and cellular mechanisms of the development of the disease, functional genomics of retinal diseases, animal models of retinal dystrophies, and finally with studies on gene therapeutic approaches to correcting the disorder. With contributions by many of the leading researchers worldwide, this book is likely to be an important milestone in this rapidly developing field.

Much recent research in evolutionary developmental biology has focused on the origin of new body plans. However, most evolutionary change at the population and species level consists of tinkering: small-scale alterations in developmental pathways within a single body plan. Such microevolutionary events have been well studied on a population genetic level and from the perspective of adaptive phenotypic evolution, but their developmental mechanisms remain poorly studied.

This book explores both theoretical and practical issues of tinkering. It features a wide range of perspectives to address several fundamental questions. How does tinkering occur developmentally, and how is it manifested phenotypically? Are the developmental mechanisms by which tinkering occur different from those that underlie larger evolutionary changes? What are the developmental constraints on tinkering? And how do we test hypotheses about microevolutionary shifts in development from the fossil record?

With contributions from experts in a range of fields, this fascinating book makes exciting reading for anyone studying evolution, developmental biology or genetics.

Dietary supplements can contain a wide variety of ingredients, either singly or in combination, including nutrients, botanicals and ''bioactive components'' commonly found in foods. They are marketed and used by consumers for a range of reasons: to enhance "well-being", as traditional medicines, for health promotion or disease risk reduction, and as alternatives or complements to conventional drug therapies.

On a global basis, the dietary supplement industry has enjoyed rapid growth, becoming a multi-billion dollar enterprise over the last 10 years. This growth has been associated with significant changes in both the types of products available and the reasons for using these products.

In many cases, these changes have occurred without the benefit of a sound scientific basis for evaluating the safety and efficacy of these products under the new conditions of use and frequently the same limited scientific evidence is used, even though current product composition, user populations, purported beneficial effects, and conditions of use may differ significantly from the available evidence or historical usage.

This book presents systematic examinations of the scientific data that are available and/or needed to substantiate and evaluate the safety and efficacy of dietary supplements. A series of case studies that are illustrative of the types of scientific challenges that have been encountered in substantiating safety and efficacy for various product types are employed to point out some of the successes but also frustrations that have occurred in recent years. Discussions among presenters and participants identify the lessons learned from these experiences and formulate ideas for improved approaches to identifying research needs and for enhancing the quality and relevance of the scientific evidence available for policy decisions.

Dietary Supplements and Health constitutes a useful resource for nutritionists, biochemists, public health researchers and anyone interested in herbal, alternative medicines.

Ciba Foundation Symposium 123 Antidepressants and Receptor FunctionChairman: Dennis Murphy, 1986

Depression is a common and often debilitating affective disorder. Attempts to develop effective antidepressants have a long history, but many questions remain about the mechanisms of action of such treatments and about the aetiology and pathophysiology of depression itself. Early observations centred attention on central monoamine systems, and animal studies suggested that changes in beta-adrenoceptor responsiveness were a common effect of antidepressant therapies. More recent research has encompassed many different central and peripheral receptors, time-dependent adaptational events at synapses, and the functional significance of changes in neurotransmitter systems in both humans and experimental animals. Such pharmacological studies aimed ultimately at elucidating the neurochemical basis of depression and of promoting new therapeutic approaches, provide the focus of this symposium volume. Many different methods of investigating the links between monoamine systems, depression and antidepressant treatments are described. Recent studies of receptors and of monoamine uptake sites in the brain and the periphery (e.g. in platelets and fibroblasts) are reviewed, with emphasis on alpha and beta adrenoceptors, [3H]imipramine-binding sites and serotonin receptors. The results of monitoring amine metabolites in cerebrospinal fluid and of measuring neuroendocrine, physiological and behavioural responses to pharmacological challenge are presented, providing information on monoaminergic function in depressed patients and experimental animals before, during and after treatment with antidepressant drugs or electroconvulsive shock. Genetic influences on receptor density are also discussed, as is the relevance to human depressive illness of animal models, including stress-induced behavioural depression in rats and responses to social stressors in rhesus monkeys.

This book should be of interest to neuropharmacologists, psychopharmacologists, clinical pharmacologists, behavioural scientists, psychiatrists and neuroscientists.

Epithelial cells cover the outer and inner surfaces of the body, forming a selective polarized barrier between the intercellualar space and the ''external'' world. Linking the cells of this continuous layer and contributing to epithelial organization and function are specialized membrane domains--desmosomes, gap junctions, and occluding junctions. The contributors to this multidisciplinary symposium volume explore the nature of such junctional structures, focusing on the molecular organization and diversity of their constituent proteins, their formation and control, and interactions with ions and cytoskeletal elements. The physiological significance of cell-cell interaction in epithelia is considered, with reference to cell adhesion, barrier formation and intercellular communication, and to the functional implications for tissue architecture, embryonic development, morphogenesis and carcinogenesis.

Parkinson''s disease, Alzheimer''s disease, and motor neuron disease share a significant common feature: selective death of neurons in restricted regions of the brain. This international symposium, held by the Ciba Foundation in 1986, is the first to bring together neurophysiologists working on neuronal death and neuropathologists dealing with human degenerative brain disease. Participants describe the causes and sequence of events leading to neuronal death and discuss what can be done to prevent it. Among the topics covered are recent advances in the understanding of agents such as trophic factors, excitotoxins and poisons that are known to be involved in neuronal death; examples of neuronal death during normal development; and the role played by endocrine mechanisms and neuronal activity. Also considers trophic factors controlling the survival of neuronal transplants and the therapeutic prospects for tissue transplantation.

Until recently a neglected disease syndrome, diarrhea is responsible for many millions of infant deaths in developing countries. The result of a 1987 symposium, this volume reflects advances in the aetiology of diarrhea while addressing such puzzling problems as the difficulty of growing viruses in a controlled setting. The volume is deliberately restricted to so-called ``novel'''' diarrhea viruses and is not concerned with ``classical'''' rotaviruses, which have formed the basis of previous symposia. Articles concentrate on: atypical rotaviruses; the enteric adenoviruses; small round viruses such as astroviruses, caliciviruses and Norwalk virus; and the Berne and Breda viruses, suggested as a new family Toroviridae. The contributions come from an interdisciplinary mix of virologists (both human and veterinary), epidemiologists, molecular biologists, and pathologists.

Many common human diseases have a multifactorial origin: they are influenced by a person''s genetic predisposition as well as by factors in the environment. This volume deals with the application of recombinant DNA techniques to the identification of diseases that have more than one inherited component. Focus is on the polygenic factors responsible for coronary atherosclerosis. Several other disorders having a polygenic origin are also discussed, including hypertension, diabetes mellitus, psychiatric diseases, and autoimmune (HLA-related) disorders. Problems raised by the study of different families or different populations are covered, as well as the possibility of applying molecular techniques to disease prevention--for example, through gene therapy. Also, some of the ethical issues that relate to human gene mapping are briefly explored.

The number of factors implicated in the regulation of cell proliferation and differentiation is already considerable and more are continually being identified. This book concentrates on tumor necrosis factor (cachectin) and lymphotoxin, but includes observations of their interactions with other cytokines, especially the interferons and interleukins. TNF can be either cytostatic or cytotoxic to cultured cell lines, and a variety of mechanisms are proposed, ranging from DNA fragmentation to activation of phospholiopases. TNF is also reported to stimulate the growth of normal fibroblasts in vivo. The in vivo actions of TNF described here include haemorrhagic necrosis of tumors, cachexia, effects on the vasculature, and antiparasitic and antiviral activities. Also presented is some interesting data from the first stages of clinical trials of TNF as an anticancer agent.

Comprises the proceedings of a symposium held at the Ciba Foundation, London, February 1987. Addresses main issues and new techniques in the study of motor areas of the cerebral cortex in humans and animals. Reviews the historical development of the study of cortical structure and function, examines anatomical connections of motor areas, and surveys physiological studies of cortical areas in conscious primates. Also considers the effects of cortical lesions, and discusses clinical and experimental results on disorders of motor control.

The term "unconventional virus" refers to virus-like agents that differ from conventional viruses in significant respects--resistance to agents that inactivate normal viruses, for example. Certain rare and fatal neurological disorders, such as the Creutzfeldt-Jacob syndrome and the Gerstmann-Straussler syndrome, are clearly produced by virus-like infectious agents, but the nature of these agents is not understood. This volume brings together the latest information on one such disease: Scrapie, a disease occurring in sheep. It discusses the nature of this infectious agent and insights gained through new techniques in molecular genetics. The work as a whole focuses on the implications of animal data for research on human disorders, such as the possible connection between unconventional viruses and Alzheimer''s Disease. The discussions represent the work of specialists from a broad spectrum of fields including virology, neuropathology, and molecular biology.

This work deals with basic plant physiology and cytology, and addresses the practical exploitation of plants, both as crops and as sources of useful compounds produced as secondary metabolites. Covers problems of commercial exploitation, socio-legal aspects of genetic engineering of crop plants, and of the difficulties of marketing natural compunds produced by cells under artificial conditions.

Regulation of intracellular pH is vital to all living cells. This symposium covers the control of pH in muscle and nerve cells and the different mechanisms of acid transport across epithelial and other cell membranes. Papers describe the development and application of microelectrodes and various techniques in molecular biology to the study of the mechanisms of protein transport. Also discusses the significance of pH regulation for the action of hormones and growth factors.

An international group of researchers addresses basic mechanism involved in the metastatic spread of tumors and considers new methods of prevention and treatment. Compares behavior of normal and abnormal cells, with emphasis on cell surface mechanisms--especially invasive processes--and inhibitors that might prevent metastasis. Also discusses determination of the metastatic genotype, the role of the immune system, and reduction of metastasis via liposome-activated macrophages.

Comprises the proceedings of a symposium held at the Ciba Foundation, London, February 1988. Contains the latest research results on the inverse relationship between cell proliferation and differentiation and the nature of the genes involved. Included are the studies of cell fusion experiments, the introduction of single chromosomes into malignant cells, and the transfection of individual genes. Also reports on the role of certain oncogenes in normal development, lineage commitment, and tumorigenesis.