Public health genomics: The end of the beginning

In the 20-year journey of the American College of Medical Genetics, public health has had an important influence on the emergence and progress of genomic medicine. This influence can be readily discerned on the pages of Genetics in Medicine, the official journal of the College. As the journal's section editor in public health, I write this special anniversary commentary on the heels of the fourth national conference on genomics and public health, held in Bethesda, MD, in December 2010.¹ The conference was attended by more than 500 people from multiple sectors including academia, industry, state and federal government, consumers, and the media, all interested in the translation of genome-based discoveries into health benefits now and in the future. The conference represented more than a decade-long progress in establishing the field of public health genomics as a scientific foundation for using genetic information to improve the health of populations. In a time of economic downturn and shrinkage of public health at the federal, state, and local levels, more resources will be shifted toward emergency programs and services with immediate health impact. Therefore, investments in public health genomics in 2011 are at an all-time low. This may be attributed, in part, to the fact that the promise of genomic medicine is still largely unfulfilled, and as such, genomics has not demanded the urgency of public health action today. Yet, if the promise of genomics is to be realized in the next decade, public health will have to play, as it has done in the past decade, an important leadership role. In this commentary, I revisit the basics of public health genomics and how the field has been represented in Genetics in Medicine. I use the three essential public health functions and priorities in genomics as discussed elsewhere²: (1) policy development function and public health's unique “honest broker” role, (2) assurance function and public health's role in implementation and evaluation of services, and (3) assessment function and the role of multidisciplinary population sciences in assessing impact and value of genomic information in health and health practice. Public health genomics in 2011 is more important than ever in realizing the health benefits of human genome discoveries in the 21st century.

WHAT DOES PUBLIC HEALTH HAVE TO DO WITH GENOMIC MEDICINE?

The emergence of genomic medicine represents a shift from traditional medical genetics with its focus on rare genetic diseases toward more personalization in the practice of medicine and prevention of common diseases.² As such, many have questioned the role of public health in this enterprise. After all, the mission of public health is to improve health from a population perspective and its unit of intervention is the “population,” an approach seemingly at odds with the “one person at a time” vision of genomic medicine. Some suggest that applications of human genomics will be made at the clinical level, not through population screening. Some have even argued that there will be very little role for genomics in public health once we know the environmental and social causes of disease.³ Indeed, in a time of diminishing resources, new technologies can divert needed resources away from what can be done today in delivering basic public health services and addressing social and environmental determinants of disease.³ However, the practice of genomic medicine (and medicine in general) occurs at multiple levels of intervention including patient-provider dyads, healthcare organizations, families, communities, and state and federal policies and regulations, all appropriately viewed by the Institute of Medicine as part of the “public health system.”⁴ Moreover, as genomics ventures more and more into primary prevention and health promotion with the emergence of the direct-to-consumer movement,⁵ we are going to see an increasing role for public health practitioners in providing health education information and policy frameworks for protecting consumers and minimizing costly and unnecessary healthcare expenditures. Because public health has a population focus with an eye toward the most vulnerable segments of the population,⁶ it will have a major role in ensuring the success of genomic medicine. The contributions of public health center on the applications of essential public health functions and services: assessment, policy development, and assurance. The three essential public health functions were first discussed by the Institute of Medicine in 1988⁷ and elaborated on over the years including in the area of genomic medicine,^8,9 most recently by the Association for State and Territorial Health Officials in their 2010 genomics and public health report.¹⁰ The public health functions provide an important basis for providing an appropriate balance between the forces of “premature translation” (i.e., use of nonvalidated or potentially harmful genomic information in practice) versus “lost in translation” (i.e., the endless study and evaluation of new technology with limited access across the population).²

PUBLIC HEALTH GENOMICS IN ACTION

Table 1 revisits the definitions and applications of public health functions as they relate to genomic medicine, superimposed on a list of near-term priorities for public health action recently discussed by Khoury et al.³ Over the past decade, Genetics in Medicine has published many public health genomics articles that represent applications of public health principles and approaches to the development, evaluation, and dissemination of genome-based information in improving health and preventing disease. Table 1 lists a few illustrative examples of publications under each category.

Table 1 Contributions of public health to genomic medicine: Examples of publications in Genetics in Medicine

“Policy development” in public health includes “the formulation of standards and guidelines, in collaboration with stakeholders, which promote the appropriate use of genetic information and the effectiveness, accessibility, and quality of genetic tests and services.”⁹ An important priority for public health in genomics is as a convener and honest broker to inform providers, the public, and policy makers whether the deployment of technology for a particular intended use can have a net positive health impact on the population. Because of the potential for conflicts of interests among various groups, public health can serve as an unbiased convener of stakeholders.³

The journal continues to disseminate evidence-based methods, analyses, and syntheses of information along with recommendations for action in two areas. The first is newborn screening, where the Advisory Committee on Heritable Disorders of Newborn and Children, an independent panel, has produced evidence-based recommendations on what disorders to include nationally in newborn screening, the largest public health genomics program in the United States and globally.¹¹ The second area is genomic tests in practice, where the Evaluation of Genomic Applications in Practice and Prevention working group, an independent multidisciplinary panel, has produced evidence-based recommendations on genomic tests in several areas.¹² Another example of an honest broker stakeholder convening function is the workshop conducted by National Institutes of Health and Centers for Disease Control and Prevention in 2008 on the scientific foundation for personal genomics. This workshop led to a number of recommendations and analyses published in the Journal in 2009.¹³ The Journal has also contributed to the launching of a public-private stakeholder network, the Genomic Applications in Practice and Prevention Network, that seeks to accelerate the translation of genomics into practice using stakeholder engagement and empowering translation research and programs.¹⁴ Genetics in Medicine also helped to launch an international public health genomics consortium, the Genome-based Research and Population Health International network,¹⁵ which continues to marshal resources and collaborations from several countries and institutions around the world.

“Assurance” in public health implies “assuring that genetic information is used appropriately and that genetic tests and services are used based on agreed-upon goals for effectiveness, accessibility, and quality.”⁹ Related functions involve linking patients to providers, implementing programs (e.g., newborn screening), ensuring provider and public competencies, and implementing education and policy interventions. Several examples can be highlighted here. The first is the Journal's special supplement in 2010 on long-term follow-up of individuals identified through newborn screening programs.¹⁶ Another example is the model translation program for rare disease genetic testing (collaboration, education, and test translation¹⁷). A third example is a special report by the Advisory Committee on Heritable Disorders of Newborn and Children on assuring that the primary care workforce is appropriately informed and trained in medical genetics and genomic medicine.¹⁸

Finally, “assessment” in public health includes “the regular systematic collection, assembly, analysis, and dissemination of information including human genome epidemiologic information, on the health of the community.”⁹ This area includes the use of multidisciplinary public health sciences such as epidemiologic studies of prevalence of genetic risks factors and family history, magnitude of disease risks and gene-gene and gene-environment interactions, and disease prediction. It also includes behavioral, communication and social sciences, economic analysis, health services research, comparative effectiveness and outcomes research, and public health surveillance for monitoring outcomes and investigating community concerns.

Table 1 provides several examples of public health assessment in multiple disciplines including epidemiology (e.g., population prevalence of familial cancer: data from the 2005 California health interview survey¹⁹); behavioral sciences (e.g., exploring the psychological impact of providing genetic services though cascade approaches²⁰); communication science (e.g., impact of communicating personalized genetic risk information on perceived control over the risk²¹); economic analysis (e.g., cost-effectiveness analysis of genetic testing for Lynch syndrome among all newly diagnosed patients with colorectal cancer²²); and public health surveys (e.g., national survey on use of available genetic tests among primary care physicians²³).

PUBLIC HEALTH GENOMICS: LOOKING FORWARD

In looking back to the past decade, we have seen the emergence of public health genomics, a multidisciplinary field that has established scientific and policy foundations for the appropriate translation of the new science of genomics into health benefits to individuals and populations. In the next decade, the stage is thus set for the applications of this new field with rapidly evolving tools of genomics, including whole genome sequencing and a slew of gene-based products such as gene expression profiles, proteomics, epigenomics, and metabolomics.²⁴ Increasingly, these applications will be offered to be used in treatment, early detection of diseases and primary prevention, and health promotion. Public health has already established the foundation for assessing the balance of benefits and harms of genomic applications in populations, for implementing validated applications throughout the population, and for evaluating their impact on health care and disease prevention in the United States and around the world.