Preventing Disease and Protecting Health Among Individuals at Increased Genetic Risk: A Lifespan Perspective and an Emerging Public Health Challenge

Since the completion of the Human Genome Project, major advances have occurred in the translation of human genome discoveries into clinical practice and disease prevention. As almost all human diseases are due to complex gene-environment interactions, the applications of human genomics should be pertinent to the prevention and control of many diseases, including rare and common chronic diseases.

An increasing number of genetic tests are becoming available in medical practice. As of December 14, The National Library of Medicine’s Genetic Testing Registry lists 76,546 genetic tests for 22,570 conditions involving 18,736 genes and 518 laboratories. These tests can be used in diagnosis, prognosis, therapeutic optimization (pharmacogenomics), population screening, and risk assessment. In addition, an increasing number of tests have evidence-based recommendations for improving health that are classified as tier 1 applications, which can save lives and prevent disease if implemented in clinical practice. As of July 2022, the CDC Office of Genomics and Precision Public Health has identified a total of 132 tier 1 applications covering a wide variety of diseases at every stage of life and potentially affecting millions of people in the United States. To learn more, check out our recent blog that summarizes trends in tier 1 genomic applications in the past decade.

With increasing implementation of human genomics in clinical practice, the National Human Genome Research Institute has set forth a bold vision for 2030 to have genomics firmly integrated in clinical practice.  The plan predicts that by 2030, “The regular use of genomic information will have transitioned from boutique to mainstream in all clinical settings, making genomic testing as routine as complete blood counts.” As these changes take place in clinical settings, a lifespan perspective on genomics and genetic testing can also be integrated into public health programs to better protect health and prevent disease among individuals at increased genetic risk for multiple disease conditions.

Protecting Health and Preventing Disease Across the Lifespan

The risk for developing various diseases is impacted by variations in our genome and their interactions with the environment at large across the lifespan. This implies that genomics and genetic testing may provide health benefits at every stage in life for all healthy individuals and those with various medical conditions.  In her recent review of advances in genomics Heidi Rehm states, “From conception  and prenatal health, to  elderly care, we now have access to genomic technologies and to the information our genomes provide to personalize and inform precise approaches for optimizing our health and for combating disease.” (see Figure 1 in the paper)

The table below summarizes examples of the current landscape and emerging applications of human genomics in health and health care across the lifespan. As we can see, the relevance of genetics continues throughout life, from preconception and prenatal health to infancy and childhood, and through every stage to follow. While we cannot adequately capture here the details of all genomic applications across the lifespan, we refer our readers to our webpages, blogs and papers on these various topics (see selected links in the table).

Opportunities for Public Health Practice

A major challenge in the implementation of human genomics to improve population health is that its integration needs to occur in almost all public health programs and across the life stages. As outlined in the table, many of the near-term applications of human genomics touch on various public health programs within CDC and beyond (birth defects and developmental disabilities, reproductive health, newborn screening, child and adolescent health, and adult chronic diseases, such as cancer, diabetes and heart disease). In public health, a lifespan approach has already been adopted by several programs focused on birth defects (e.g. congenital heart defects), occupational health, and cancer; but there are many additional opportunities for implementation. Newborn screening provides one example of the rapid integration of genomics into public health. In our recent blog, we discussed the evolution of newborn screening as it moves beyond its 60^th anniversary in the US. Our understanding of the thousands of rare diseases, many with underlying genetic basis, has grown and the potential for use of genomics has become more feasible leading to a heightened call for the evolution of newborn screening. This has led to the development of both public health and private programs that are assessing the clinical utility of expanded newborn screening using next-generation sequencing.

Addressing Disparities in Genomics and Genetic Testing

As advances in human genomics are not readily accessible to all, striking disparities occur.  It is imperative that public health leaders approach this rapidly evolving environment through the lens of health equity and universal access.  Currently, the implementation of genomics and precision medicine is uneven at best in the US and around the world. Our recent paper documents widening disparities and access to genetic testing and services for a number of tier 1 genomic applications, by race/ethnicity, socioeconomic status, education and urban/rural residence.

As we celebrate  25 years of public health genomics at CDC, an emerging public health challenge is to assess when and where human genomics knowledge can be integrated into public health programs to help serve individuals at increased genetic risk across the lifespan.  This integration will involve public health data modernization, enhanced policies and guidelines, as well as programs and workforce for genetic services, provider and public education, and community partnerships. As genetic information becomes increasingly used in health care, we have an important opportunity to tackle existing disparities in protecting health and preventing disease for all.

Table: Examples of Emerging Opportunities for Public Health to Protect Health and Prevent Disease Among Individuals at Increased Genetic Risk Across the Lifespan