1Office of Genomics and Disease Prevention, Centers for Disease Control and Prevention, Atlanta, GA
²School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC

	At-A-Glance
	Introduction Defining Key Concepts
	Blueprint for Integrating Genomics into Public Health Examples of Current Genomics Activities in Public Health
	Conclusions
	Acknowledgments
	References

At-A-Glance

Objectives. To examine the opportunities for and responsibilities of the public health community in bridging the gap between gene discovery and the application of genetic information to improve health and prevent disease.

Methods. We developed genetics-related definitions for the core functions and essential services of public health. We combined these definitions with a visual model to create one possible "blueprint" for integrating genomics into public health activities.

Results. The proposed blueprint and accompanying examples illustrate the important role for genomics throughout public health research, policy, and practice. Further refinement and implementation of this blueprint represents an ambitious public health leadership agenda.

Conclusions. Opportunities for immediate action include strategic planning for the integration of genomics across programs, developing genomics competencies among health professionals, enhancing surveillance and epidemiologic capacity to aid evidence-based policy making, building partnerships and seeking input from stakeholders, and incorporating information about genomics into health communications.

Introduction

During the past century, achievements in public health led to dramatic improvements in the health and life expectancy of people in the US and around the world [1]. Immunization programs and better sanitation practices resulted in the eradication or reduction of many infectious diseases and safer food and water supplies. Advances in occupational safety decreased considerably the number of work-related injuries, illnesses, and deaths. In the past 30 years, identification of behavioral risk factors, such as smoking, inactivity, and poor dietary habits, gave rise to educational interventions and a decline in death rates from certain chronic diseases.

Perhaps because of these accomplishments, the determinants of disease and disability – whether natural or human made – are often perceived as originating outside the body. Although it has long been recognized that disease generally results from a constellation of host- and environment-specific factors, scientific and technologic limits have concentrated attention on the environment. Exogenous influences will continue to be vital for public health, but focusing solely on these influences may lead to diminishing rates of return compared to the triumphs of the past. To continue making significant strides, we must strengthen the effectiveness of public health interventions by more fully incorporating knowledge of internal, host-specific factors and their interactions with environmental exposures.

Rapid advances in human genetics and accompanying technologies are making this expanded approach to public health research, policy, and practice increasingly possible. Until recently, the field of genetics was largely confined to the realm of rare disorders caused by mutations in single genes. Even so, the public health community included genetics components in some of its work, experiencing noteworthy successes in birth defects prevention [2-5], newborn screening for inborn errors of metabolism [6,7], and development of genetic services capacity [8,9]. Today, the mounting accomplishments of the Human Genome Project demand that we re-think the role of genomics in every condition of public health interest. Microarray technology, for instance, and dense maps of common human DNA sequence variations called single-nucleotide polymorphisms will be a boon for genome-wide association studies of complex disorders such as cancer, heart disease, and diabetes [10]. This information explosion is expected to bring about nothing short of a revolution in medicine and public health [11,12]. Dr. Francis Collins, director of the National Human Genome Research Institute, depicts a potential outcome of this revolution in his description of a hypothetical clinical encounter in 2010 [13]. John, a 23-year-old man, consults with his doctor in selecting from a battery of genetic tests that will provide information about his personal relative and lifetime risks for a number of common diseases:

Confronted with the reality of his own genetic data, [John] arrives at that crucial "teachable moment" when a lifelong change in health-related behavior, focused on reducing specific risks, is possible. And there is much to offer. By 2010, the field of pharmacogenomics has blossomed, and a prophylactic drug regimen based on the knowledge of John’s personal genetic data can be precisely prescribed to reduce his cholesterol level and the risk of coronary artery disease to normal levels. His risk of colon cancer can be addressed by beginning a program of annual colonoscopy at the age of 45, which in his situation is a very cost-effective way to avoid colon cancer. His substantial risk of contracting lung cancer provides the key motivation for him to join a support group of persons at genetically high risk for serious complications of smoking, and he successfully kicks the habit [13].

In the excitement about this kind of vision for genetically-based, individualized prevention, however, it is easy to overlook the immense gap between the scientific products of the Human Genome Project and the ability to use genetic information to benefit health. Information about genes and DNA sequences must be translated into knowledge about genetic susceptibility to disease and the interactions between these susceptibilities and modifiable risk factors. We must also formulate policies that will promote the safety, accessibility, and quality of genetic tests and services and develop effective programs for targeting interventions to people at increased risk. Bridging this gap – the "Grand Canyon" between advances in human genetics and the application of genetic information to improve health and prevent disease – requires a wide range of activities drawing upon all of the core functions and essential services of public health.

How then should the public health community approach the task of translating the already-occurring deluge of genetic discoveries into public health action? How can public health agencies prepare their workforce and their constituencies to ensure that information about gene-environment interactions is used appropriately? The prototypical public health paradigm in genetics has been newborn screening and we can learn much from these experiences. However, the "new" genetics calls for even greater partnership and coordination between clinical medicine and public health activities. While much genetic testing and screening may one day take place as Dr. Collins describes – in a clinician’s office on an individual basis – public health researchers must analyze genetic information on a population level in order to inform health policy and program development. The public health community must work with public and private health care sectors to ensure that genetic tests are valid, available, and accessible – especially in underserved populations – and to assure that individuals in the population have access to proven interventions. Public health professionals also have a crucial role in educating other health professionals and stakeholders and in evaluating the impact and cost effectiveness of integrating genomics into health promotion and disease prevention programs.

To highlight the requirements of the new genetics, we have developed definitions for the role of genomics in each of the public health functions and services. We propose these definitions here together with a visual model, thus creating one possible "blueprint" for integrating genomics into the complete range of public health activities. We include examples of current genetics-related activities in the US within each of the essential services to stimulate discussion regarding how genomics should be incorporated throughout public health research, policy, and practice.

Defining Key Concepts

This blueprint uses several key terms. Human genome epidemiology is the study of the role of genetic factors and their interaction with environmental factors in the occurrence of disease in human populations [14,15].  Stakeholders are all groups of people with an interest in the use of genetic information, such as the general public, patients, support and advocacy groups, health professionals, scientists, policy makers, and pharmaceutical, biotechnology, and insurance industry personnel.  Public health infrastructure consists of the resources needed to deliver the essential public health services to every community [16].  Gene variant refers to both heritable mutations and polymorphisms.  Environmental factors encompasses all exogenous factors – chemical, physical, infectious, nutritional, social, and behavioral.  Finally, prevention means the use of environmental interventions to reduce the risk of disease among people susceptible because of their genetic make up.

Blueprint for Integrating Genomics into Public Health

In its landmark report, The Future of Public Health, the Institute of Medicine (IOM) defined three core functions of public health: assessment, policy development, and assurance [17]. To operationalize these core functions, several groups developed more specific descriptions of public health processes, including a list of 10 essential services [18]. We use these functions and services as a foundation for our blueprint, both as a way to demonstrate the merger of genomics into existing public health activities and to emphasize that genetics is not an isolated specialty requiring a separate framework. This approach is in accordance with previous commentary by a Genetics Working Group at the Centers for Disease Control and Prevention (CDC), which used the IOM paradigm to examine the continuum from genetic technology to public health practice [19], and with CDC’s agency-wide strategic plan for genetics activities [20].

The blueprint is proposed as a nonprescriptive tool to promote dialogue and to assist public health professionals at federal, state, and local levels to effectively and systematically integrate genomics into public health research, policy, and practice. It may also be helpful for educating other key stakeholders, such as policy makers, about the use of genomics to improve health and prevent disease. It is intended to encompass both single-gene disorders and complex diseases involving multiple genetic and environmental factors. It is based on the US health system and would need to be modified for use in other contexts.

The blueprint comprises the visual model and genetics-related definitions proposed in the following section, "Examples of Current Genomics Activities in Public Health."  The visual model is based upon that created by the Public Health Functions Team [21], which we adapted as follows:

The traditional list of 10 essential public health services includes "research." In this broad sense, we define public health research involving genomics to mean: A systematic investigation designed to develop or contribute to generalizable knowledge of the impact of human genetic variation on health and disease. The visual representation created by the Public Health Functions Team places research in the center, as the hub of a "wheel" of public health services. This illustrates how research provides the scientific underpinnings that enable each of the other services. To highlight the array of research activities needed to integrate genomics into public health, we segmented "research" into three areas of inquiry corresponding to the three core functions as shown below.

As the visual model suggests, performance of the public health functions and services is neither linear nor discrete. Assessment activities provide the knowledge base for policy development concerning genomics and for assuring the proper implementation of programs and services that involve genomic components. Policy development activities help identify gaps in scientific knowledge and form the foundation for assuring the effectiveness, accessibility, and quality of programs and services. The assurance function, in addition to ensuring that genomics is properly integrated into health-related services, also supplies evaluative information for continuing efforts in assessment and policy development.

Examples of Current Genomics Activities in Public Health

Here we provide brief descriptions and examples from the US to demonstrate practical applications of the genetics-related definitions. These examples are not intended to be comprehensive or even representative of all current or potential genomic activities in public health, but to stimulate further discussion and development of the blueprint for integrating genomics into public health research, policy, and practice.

There are three ways to view this information:

1. Explore the links in the visual model below to see the genetics-related definitions.

2. Click on any of the major components below to see all of the information – definitions, descriptions, examples –  about that component:

• Research
• Assessment
• Policy Development
• Assurance
• System Management

3. Click on any of the essential services below, which we have arranged in roughly chronological order – beginning with those most important for initial planning, preparation, and training followed by those that come into play primarily as specific applications of genomic information arise:

• Research
• Mobilize Partnerships
• Assure Competent Workforce
• Inform, Educate, Empower
• Develop Policies
• Monitor Health
• Diagnose and Investigate
• Enforce Laws
• Link to / Provide Care
• Evaluate

Conclusions

Rapid advances in human genetics and accompanying technologies are making it possible to explore the full constellation of factors that affect human health and disease – external influences as well as internal, host-specific factors. Understanding the impact of environmental exposures on people who carry specific gene variants offers the possibility of more effective public health interventions targeted to those who are most susceptible to particular diseases. These range from diseases affecting the health of infants and children to adult chronic diseases to disorders stemming from exposure to infectious agents or environmental hazards. Our challenge is to translate gene discoveries into opportunities to improve health and prevent disease in a way that maximizes the benefits of using genetic information, minimizes the risks, and conserves health care resources.

We have proposed here one possible blueprint for integrating genomics into the full spectrum of core functions and essential services of public health in the US. This blueprint demonstrates the important role for genomics throughout public health research, policy, and practice – not as a separate specialty but as a fundamental component of existing disease prevention and health promotion programs. Further refinement and implementation of this blueprint and others like it represents an ambitious public health leadership agenda. Recommendations for immediate action include the following:

1. An urgent priority for state public health agencies is to develop a sound strategic plan that supports the integration of genomics across its programs. Such plans should be shaped by input from every branch of the organization, including maternal and child health, environmental health, chronic disease, laboratory services, and infectious disease.

2. A key component of the successful assimilation of genomics into public health will be to train the workforce. Strong partnerships between schools of public health, academic genetics centers, professional organizations, industry, and government agencies will ensure the development of genomic competencies and skills among current and future public health professionals.

3. The public health community will need to enhance surveillance and epidemiologic capacity to collect and analyze the information flowing from community-based assessments of the impact of genetic variation on the burden of various diseases and from the evaluation of genetic tests and services. These data will allow health care providers and policy makers to make evidence-based decisions about the appropriate use of genetic information to improve health and prevent disease.

4. Public health professionals must build partnerships with and seek continuous input from stakeholders such as community groups and professional organizations. This can be accomplished in many ways (e.g., advisory committees, task forces), and the best avenues for communication may be different for different diseases.

5. Finally, it will be crucial for public health agencies to communicate about genomic issues to policy makers, health professionals, and the general public. As in other areas of public health, communication messages must be developed for a variety of audiences to educate and empower them regarding the role of genetic information in disease prevention and health promotion.

We gratefully acknowledge the following people for their contributions to the blueprint and for their comments on previous drafts of this paper: Marta Gwinn, Elizabeth Gettig, Amanda Brown, and the members of CDC’s Genetics Implementation Team.

This project was supported in part under a cooperative agreement from CDC through the Association of Teachers of Preventive Medicine .

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