Navigating the DNA Roadmap: Genetic Testing and Health Behavior Change
Navigating the DNA Roadmap: Genetic Testing and Health Behavior Change originally appeared on the Envolve PeopleCare blog on December 14th, 2017.
St. Louis, MO – Today, a woman born in the United States has a 1 in 8 chance of being diagnosed with breast cancer in her lifetime – a staggering 252,710 women in 2017. Even for men, who have a 1 in 1,000 chance of being diagnosed, 2,470 diagnoses are expected this year1. But would these numbers change, or even decrease, if people knew whether or not they are genetically more likely to develop breast cancer? Researchers are working to answer this very question and understand how and if genetic testing impacts health behavior change.
How We Got Here
Once inaccessible to most, DNA mapping has become increasingly available in the decade following the sequencing of the human genome in 2003.2 While genetic testing has been used for close to a century in various forms, the focus has recently spread to personal, more preventive uses. From as little as a saliva sample, the analysis of a person’s DNA creates a genetic roadmap, showing the different paths an individual’s health may take over the course of their lifetime. These results can indicate, for example, a person’s predisposition for breast cancer, Alzheimer’s, and even how well (or not) their body tolerates and processes different dietary components.
What the Research Shows
Though genetic testing has become increasingly available, research connecting knowing your genetic risk factors and health behavior change is relatively new. In other words, the jury is still out on whether predisposition toward certain conditions or having certain genetic markers spark long-lasting changes in health behavior.
Some researchers argue yes, that individuals switch their behaviors to account for the possibility of a diagnosis later in life. For example, the REVEAL study found that individuals with a predisposition for Alzheimer’s altered their daily actions to include recommendations on disease prevention and worked with their insurance to ensure long-term coverage.3 Others argue no, pointing to a study that found individuals who process sodium and other dietary factors less efficiently lost the motivation to maintain healthy behavior changes over time.4,5
Another notable study in this area looked at genetic testing for pre-symptomatic Huntington’s disease (HD). Researchers found that even for those with a family history of HD, pre-symptomatic testing is rare. However, the rate of genetic testing dramatically increases following symptom onset. So in addition to looking into how genetic testing contributes to health behavior change, this study opens the door for additional research to understand better who is choosing to have their DNA sequenced and why.6
In short, while some question the use of genetic mapping as a method for changing health behavior, others argue that more time and research is necessary to unlock genetic mapping as a powerful method for impacting behavior for certain diagnoses and individual motivation.
The good news, at least for people interested in health behavior change, is that while the research is divided on whether or not the results of genetic testing will motivate positive health behavior changes, there is no evidence that genetic testing results lead to negative health behavior changes either.7
Despite inconclusive reviews about the intersection of genetic mapping and health behavior change, there is no question that genetic mapping has solidified its position as an up-and-coming methodology in the academic, medical, and personal arenas. Genetic mapping companies are offering gene sequencing for increasingly more affordable rates as testing becomes more common and the price for DNA sequencing is driven down. This means individuals are able to get the results of their DNA sequence on their own time and choose to alter their health behaviors as they see fit.
Though the impacts of learning one’s genetic information remains highly variable, it will be increasingly important at the individual and societal level to examine how social norms and health education intersect with the phenomenon of more people learning of possible genetic predispositions for certain conditions or diagnoses.
The opportunity also exists for genetic mapping to align with broader health efforts moving toward prevention. As research and knowledge in this area expands, the health and medical field can adapt not only to offer information about DNA results, but also to compliment people’s curiosity about their genetics to support and encourage them to make healthier life choices. Properly supplemented, information gained from genetic mapping has the potential to lead to positive health behavior change. As time passes and genetic testing becomes even more accessible, robust research and evaluation will be critical not only to understand better the human genome, but how to turn knowledge of genetics into action.
1Breastcancer.org. (2017). U.S. Breast Cancer Statistics. Retrieved 2017, from http://www.breastcancer.org/symptoms/understand_bc/statistics
2Bickel, P.J., Brown, J. B., Huang, H., & Li, Q. (2009). An overview of recent developments in genomics and associated statistical methods. Philosophical Transactions of the Royal society, 367(1906), 1-25.
3Chao S, Roberts JS, Marteau TM, Silliman R, Cupples LA, Green RC. (2008). Health behavior changes after genetic risk assessment for Alzheimer disease: the REVEAL study. Alzheimer Dis. Assoc. Disord. 22(1): 94–97
4Nielsen, D. E., & El-Sohemy, A. (2014). Disclosure of Genetic Information and Change in Dietary Intake: A Randomized Controlled Trial. PLoS ONE, 9(11). Doi: 10.1371/journal.pone.0112665
5Bloss, C. S., Madlensky, L., Schork, N. J., & Topol, E. J. (2011). Genomic information as a behavioral health intervention: can it work? Personalized Medicine, 8(6), 659–667. http://doi.org/10.2217/pme.11.73
6Oster, E., Shoulson, I., & Dorsey, E. R.,. (2013). Optimal expectations and limited medical testing: Evidence from Huntington Disease. American Economic Review, 103(2): 804-30.
7Hollands, G. J., French, D. P., Griffin, S. J., Prevost, A. T., Sutton, S., King, S., & Marteau, T. M. (2016). The impact of communicating genetic risks of disease on risk-reducing health behaviour: systematic review with meta-analysis. BMJ,352, I1102. doi:10.1136/bmj.i1102