INTRODUCTION: TRANSITIONS IN PUBLIC HEALTH GENOMICS
Over the past 20 years, the field of genomics and public health genomics has changed rapidly. The sequencing of the first human genome, complete in 2003 and costing approximately ∼$2 billion dollars, catalyzed monumental and wide-ranging shifts in research, technology, medicine, public health, business, and law. For example, technology and informatics have progressed to a level where sequencing of individual genomes is now becoming commonplace, costing only ∼$1000 per person for high-quality sequence. With large amounts of new genomic information flowing into research across many disciplines, it is fundamentally changing our understanding of human variation and its relationship to disease globally.
We are at the very beginning of cataloging all the different genome variation being discovered along with annotating their molecular characteristics and distributions across populations and across an individual’s genome. Moreover, the analysis and interpretation of the health consequences of the millions (soon to be billions) of DNA sequence variants discovered will remain a major challenge. National and international projects are sequencing 100,000s–1,000,000s of genomes and integrating them with clinical and epidemiological data to discover new genes for important health outcomes and to begin to assess clinical validity/utility. However, the translation of new genomic knowledge into improvements in health has been relatively slow for a variety of reasons, including the difficulty in estimating the clinical and population relevance of mutations and determining the appropriate use of this new genetic information within the economic and legal landscape of today’s healthcare and public health sectors.
In this chapter, we cover key concepts used to talk about genetics in populations and provide an overview of key advances in genomics as they are applied clinically and in public health settings, using the lens of primary, secondary, and tertiary prevention. In particular, we will discuss examples of genetic testing and how they differ across the lifespan. We will also explore the use of genetics in common diseases—specifically, heart disease and cancer. Then, we will provide an overview of the CDC’s Public Health Genomics program’s tiered system for moving newly discovered variants into a process of evaluation of clinical validity and utility, and how it aligns with core public health functions. Major ethical, legal, and social issues underlying the integration of genetic knowledge into healthcare and public health practices will be described. Finally, we will discuss how shifts in population health infrastructure (e.g., health information exchanges) along with low-cost genomic information could give rise to a whole range of precision health advances from precision prevention to precision medicine to precision population health.
The “genome” may be considered as the set of genes carried by an individual. The human genome has evolved as an efficient mechanism for perpetuating the human species and maintaining human health since the earliest hominids arose in Africa 3.6–4 million years ago.1 Conserved genetic sequences, maintained by natural selection, help to ...