Nutritional Genomics: Emerging Science with Implications for Us All

Abstract

Among our profession’s greatest strengths is our ability to translate science into plain language and practical action on behalf of our patients, clients, and communities. To work at the top of our ability, we need a strong grounding in critical thinking—to see the proverbial forest for the trees—especially in complex, emerging areas of nutrition science. Nutritional genomics provides an excellent example. Two sessions at the 2017 Food & Nutrition Conference & Expo drew large numbers of attendees who asked great questions, illustrating members’ interest in the potential impact of genomics on dietetics practice. The Academy is scrutinizing available evidence related to the use of nutritional genomics in practice. Does science support counseling patients or clients, according to the presence or absence of certain gene variations? Through the Evidence Analysis Library, the Academy is conducting preliminary research to determine whether there is enough literature available on this topic to warrant a systematic review, potentially leading to a revised position paper on nutritional genomics. (The Academy’s most recent position on genomics, which expired in late 2016, contains a great deal of information that is still useful to members.) As this important work continues, many resources are available for members to learn more about nutritional genomics. The Journal published a specialty collection of articles “designed to address the educational, professional, and practical needs of the dietetics professional in this rapidly changing arena.” (A topic collection of these articles can be found online at http://jandonline.org/content/nutritionalGenomics.) Ruth DeBusk, PhD, RDN, an author of two of the articles, served as the coordinating editor for the series. “Nutritional genomics will ultimately become an essential component of effective nutrition therapy, particularly for chronic disorders where food and other lifestyle choices influence gene expression,” DeBusk says. “Genomics concerns our genetic makeup and how our genome sets the stage for our functional abilities, but is only part of the story. Epigenomics concerns how our day-to-day lifestyle choices communicate with our genome and influence how well we function—whether we’ll be on the health or the disease end of the health continuum.” DeBusk has employed genomics in both clinical and education settings. “In clinical practice, I’ve used genomics to detect genetic susceptibility for particular single gene disorders as well as complex chronic diseases. In teaching primary care physicians, I use pharmacogenomics to teach the influence of genes on patients’ ability to metabolize drugs and have them see the similarities to nutritional genomics,” she says. “As the science progresses, I’m looking forward to using genome scans to identify an individual’s risk of disease and potential for health and help them optimize their genetic potential,” DeBusk says. The Academy’s 2006-2007 President, Judith A. Gilbride, PhD, CDN, FADA, FAND, has been involved in genetic aspects of nutrition and dietetics since she was a graduate student, working with inherited metabolic diseases in a clinical research center including young patients with Prader-Willi syndrome and homocystinuria. “Later on,” she says, “when I became an educator, and excitement about the human genome project grew in the press and the medical community, I wanted students and dietetics graduates to become excited, too. There were single-gene conditions like PKU [phenylketonuria] that could be treated with diet. But how soon in the future would we be able to understand diet/genotype in multifactorial diseases—obesity, diabetes, cancer, and heart disease?” Gilbride believes strongly that education of current and future practitioners is vital “to infuse nutritional genomics into nutrition and dietetic practice as new research is discovered. Personalized counseling, high-output computer DNA sequencing, expanded food composition tables with bioactive food components, food marketed for specific genotypes—these are all predicted to help consumers navigate their risk of disease and weigh genetic susceptibility.” I asked Gilbride and DeBusk about the future of genomics as it relates to dietetics: How can registered dietitian nutritionists and the Academy make our mark in this field? “We know the potential of nutritional genomics to personalize and predict nutritional needs and dietary requirements is promising, yet progress is still in its formative stages,” Gilbride says. “Diet may become one of the most important environmental factors modulating gene expression throughout the life span.” According to DeBusk, “Genomics, epigenomics, proteomics, metabolomics, microbiomics, pharmacogenomics, etc, will give rise to an era of precision health in which health care professionals will increasingly personalize therapeutic interventions to the ‘omics’ of the individual.” Lifestyle choices, particularly food choices, will emerge as powerful tools for restoring health and for preventing disease. We are uniquely positioned to make major contributions in this coming era of nutritional genomics.