Imagine that on the day you are born, a detailed analysis of your DNA outlining your risk for certain conditions and diseases, such as diabetes and cancer, is sent home with you. As a result, actions can be taken to help prevent you from ever developing those conditions for which you are most at risk. This is the concept behind many genetic testing startup companies. Although newborns aren’t being sent home with their DNA test results just yet, consumers are being offered a chance to get their genetic coding analyzed so they can learn more about what’s going on inside their bodies and how they can live healthier lives. However, genetic testing for consumers is a fairly new practice; so just how reliable is it?

Genetic testing is performed by sampling a person’s blood, hair, skin, saliva, or other tissue to detect gene variants that could determine their ancestry and health risks. Genetic testing startup 23andMe’s DNA test kit, for example, includes a vial for collecting a saliva sample to be mailed back to the company’s lab for analysis. In just a few weeks, the test results are able to be obtained by logging on to their Web site, and the consumers can review selected gene variants in their DNA and the conditions and diseases for which they may be at risk. According to 23andMe, 1 person in 5 develops diabetes by age 79. “Depending on your DNA, your risk may be 1 in 3, which makes factors like exercise and weight control more important,” the company’s Web site reads. 23andMe claims that people who learn about their risk for certain conditions through genetic testing can take better steps toward prevention.

The concept of genetic testing sounds great, but the industry is still in its early stages. The human genome was only completely mapped for the first time in 2001. The task took a large team of researchers about 13 years and $3 billion to complete. Former President Bill Clinton called it “the most important, most wondrous map ever produced by humankind.” A map of the human genome can lead to groundbreaking advancements in medicine and biotechnology; however, there is still much to be learned and perfected. A positive result doesn’t always mean a person will develop a disease, and a negative result doesn’t guarantee that a person won’t develop one. An investigation into 23andMe and its former competitor, deCODEme, found that while the 2 companies used similar methods to predict a person’s risk for disease, the test results differed by more than 50%. The gene variants that affect a person’s risk for disease are most likely multiple, and only a few for each disease are even known. In addition, the exact effect the environment has on the propensity for disease, by interacting with a person’s genome, is also still unknown, in most cases. Thus, caution is in order regarding how a patient should interpret these results.


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The Food and Drug Administration especially has a problem with 23andMe’s genetic tests. Last month, the FDA ordered the company to put an end to marketing its product on the grounds that it is being used to diagnose diseases without government approval. In a letter written to Ann Wojcicki, CEO of 23andMe, the FDA said that its tests could lead to a potential health consequence resulting from a false positive or a false negative. The letter states, “For instance, if the BRCA-related risk assessment for breast or ovarian cancer reports a false positive, it could lead a patient to undergo prophylactic surgery, chemoprevention, intensive screening, or other morbidity-inducing actions, while a false negative could result in a failure to recognize an actual risk that may exist.” Consequently, 23andMe was forced to halt marketing and will no longer provide consumers with a medical interpretation of their results.

Genetic testing is still in its infancy, with very promising results, and there is no doubt that the industry has the potential to save countless lives through disease awareness and prevention. Genetic testing is sure to become a common practice among health-conscious consumers, allowing patients of the future to be armed with much more than just Googled information and data.

Reference

  1. 23andMe Web site. https://www.23andme.com/.
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  3. How is genetic testing done? Genetics Home Reference Web site. December 10, 2013. http://ghr.nlm.nih.gov/handbook/testing/procedure.
  4. Introduction: What is DNA? Scitable by Nature Education Web site. http://www.nature.com/scitable/topicpage/introduction-what-is-dna-6579978.
  5. Sample I. Genetic tests flawed and inaccurate, say Dutch scientists. Guardian Web site. May 30, 2011. http://www.theguardian.com/science/2011/may/30/genetics-tests-flawed-dutch-scientists.
  6. Strickland E. Should healthy people get their genomes sequenced? Discover Web site. March 8, 2013. http://blogs.discovermagazine.com/crux/2013/03/08/should-healthy-people-get-their-genomes-sequenced/#.UqDzC-LO07s.
  7. US Food and Drug Administration. Inspections, compliance, enforcement, and criminal investigations: 23andMe, Inc. FDA Web site. November 22, 2013. http://www.fda.gov/ICECI/EnforcementActions/WarningLetters/2013/ucm376296.htm.
  8. What is DNA? Genetics Home Reference Web site. December 10, 2013. http://ghr.nlm.nih.gov/handbook/basics/dna.