PUBLIC HEALTH GENOMICS HAS COME OF AGE
By Muin Khoury
By Muin Khoury
from GeneWatch 28-1 | Jan-May 2015
This special issue of GeneWatch features a number of articles on public health genomics. Topics covered include prenatal testing, newborn screening and genetic testing for adult common diseases. Cross cutting themes include consumer and provider education as well as the evolving role of genetic counseling in the era of genomics. Readers may wonder what public health genomics is all about. After all, genomics is about personalized or precision medicine, while public health pertains to population health.
The mission of public health is to ensure conditions by which people can be healthy. Public health genomics is a multidisciplinary field concerned with the effective and responsible translation of genome-based science to improve population health. Genomics can be integrated into the three core public health functions:
1. Policy development: Public health serves as a convener and honest broker, advising providers, the public, and policy makers on the potential net health impact of a particular health technology (such as genetic testing).
2. Assurance involves implementing appropriate programs (such as newborn screening), laws, and regulations; assuring access; and strengthening providers' genomic competencies and the general public's health literacy.
3. Assessment applies public health sciences to monitor and evaluate effectiveness, quality and outcomes of deployment of genomic technologies in populations.
As the promise of the Human Genome Project was mixed with unrealistic expectations, the public health community has called for a scientific approach to explore the balance of benefits and harms of advances in genomics. Public health fostered an ongoing active dialogue among basic, clinical and public health-related scientific communities, and helped develop workforce competencies for integrating new tools in practice.
There are many areas of ongoing progress in genomics, where information is making a real and immediate impact on improving health and preventing disease in populations and individuals:
Newborn Screening remains the largest public health genetics program in the world, is run by public health agencies in all 50 states in the U.S., and identifies more than 30 conditions that can affect a child's long-term health or survival. Early detection, diagnosis, and intervention in more than 12,000 babies every year helps prevent death or disability. Each year, millions of babies in the U.S. are routinely screened for certain genetic, endocrine, and metabolic disorders using a few drops of blood from the newborn's heel, or a point of care test at the bedside.
Family Health History: Even with the relentless progress in genomics, family history remains the simplest and most readily available genomic tool for disease prevention and health care across the lifespan. Family members share genes, behaviors, lifestyles, and environments that together may influence their health and their risk of disease. Most people have a family health history of some diseases (e.g. cancer, coronary heart disease, and diabetes) and health conditions (e.g. high blood pressure and hypercholesterolemia). Family health history can inform decisions to use evidence-based preventive services, such as screening for elevated cholesterol and osteoporosis. The updated Surgeon General's My Family Health Portrait tool provides consumers with a free and easy way to record their family health information; is published in several languages; and enables the information to be readily shared with family members and health care professionals.
Pathogen Genomics and Public Health: The emergence of powerful sequencing and bioinformatics tools has changed the landscape in the public health fight against infectious diseases. There are numerous uses for pathogen genomics including diagnosing infection, investigating outbreaks, describing transmission patterns, monitoring antimicrobial resistance, and developing interventions such as vaccines. In 2014 CDC launched the Advanced Molecular Detection (AMD) Initiative, which aims to build critical molecular sequencing and bioinformatics capacities at national and state levels to support public health efforts to control infectious diseases.
Genome Sequencing in Healthcare: We are now in the era of Next Generation Sequencing which includes many applications such as exome sequencing, gene panels, and whole genome sequencing. This advanced technology is increasingly utilized to identify genetic causes of rare, uncharacterized diseases, particularly childhood conditions. In addition, tumor-based genomic sequencing is used in oncology for molecularly-targeted tumor classification and gene-directed therapy. In 2013, the Blue Cross Blue Shield Technology Evaluation Center evaluated the clinical use of exome sequencing in the diagnosis of rare diseases and reported a significant uptake of the technology into clinical laboratory practice.
Finally, the recently launched U.S. Precision Medicine Initiative offers a new era of personalized treatment and health care. To enable the development of new targeted interventions, a cohort of one million or more people will be sequenced and followed up over time for health outcomes. Nevertheless, to fully realize success of this initiative, a population-based perspective is truly required. Collecting information from large numbers of people is far more informative when these people are representative of the underlying population from which individuals are drawn. Using data from convenience samples collected without regard to important factors such as race/ethnicity, age, and sex can lead to substantial selection bias and unreliable disease prediction models. Also, while precision medicine is currently focused on treatment, a compelling case can be made for giving even more attention to early detection and disease prevention. Although personalized treatments can help save the lives of people who are already sick, disease prevention applies to all of us. "Precision prevention" may be useful in using both science and limited resources for targeting prevention strategies to subsets of the population at particular risk.
In summary, the successful implementation of genomics in practice and the U.S. Precision Medicine Initiative require an active collaboration among multiple sectors including research, practice, consumers, industry and public health. Public health plays a key role in making the promise of genomics a reality by identifying evidence-based applications; informing and engaging providers, policy makers and the general public; and through effective integration into health programs.
Muin J. Khoury, MD, PhD, is Director of the Office of Public Health Genomics at the Centers for Disease Control and Prevention.
The findings and conclusions in this report are those of the author(s) and do not necessarily represent the official position of the Centers for Disease Control and Prevention.