Navigating through the genetic testing jungle
Since the completion of the Human Genome Project, the cost of genome sequencing started to free-fall. The undertaking cost approximately $2.7 billion for the US government, while currently you can order your whole genome sequence online for about $400-500! Moreover, in January 2017, DNA sequencing giant Illumina unveiled a new machine that the company says is “expected one day” to order up your whole genome for less than $100. It would mean that you might have a cheaper genetic test than a general blood test.
The rapid revaluation shows the fast development of technology – not only regarding the methods for genome sequencing but also making genetic tests widely available to the public. Currently, you can order a testing kit online, send back your cheek swab to the company, and you will get your results back in a couple of weeks. Even regulators enabled gradually the full-scale operation of DTC companies allowed to provide a range of gene reports.
As a consequence, the number of ventures offering genetic testing services is skyrocketing, and in many cases, their promises seem to be, well how to say this diplomatically, far-fetched. Do you want to know whether your kid is talented in football? Whether your grumpy moods are coded in your genes? Who is your perfect match based on your DNA? Order a DNA test! No wonder that even Stephen Colbert joked about how Orig3n wanted to organize a giveaway of free DNA tests to fans before a Baltimore Ravens game. There are hundreds of ventures trying to find their niche on the DTC genetic testing market with all available marketing means, and it is more and more difficult for customers to separate the wheat from the chaff.
The geneticists’ disclaimer
I have already had some experience with genomic tests in my life – with Navigenics, Pathway Genomics, My Gentle Labs, Futura Genetics, just to name a few. I have learned what medication would cause me a side effect; what major conditions I’m at risk for; why I have certain features such as the inability to run marathons and what can I expect from the future. I also happen to be a geneticist. My Ph.D. was about clinical genomics, an exciting field that tries to translate genetic findings of individuals into clinical implications. So, I cannot just point to a few tests and refrain people from choosing others. It is more complicated as I feel more responsibility as a geneticist and choosing a genetic test is a much bigger deal than selecting a sleep sensor.
So here, I will try to give a few directions and suggestions without favoring certain companies over others. Because basically, none of the tests on the market today is good enough for my standards. Currently, what they can scientifically offer is very limited. As Andelka M. Philip’s 2016 study explains, the majority of companies do not offer whole-genome or whole-exome scans, which means that the utility of test results for the individuals tested is inherently limited. Moreover, as many DTC genetic testing companies are on the market, as widely varies their use of genetic markers and the interpretation of the various genetic variants might also differ from company to company.
So no matter what DTC companies try to sell you, beyond ancestry, specific health risks, and limited application of nutrigenomics, you cannot get to know much more – and you should most certainly not order your drink based on genetically influenced wine recommendations. Here, I collected those DTC genetic testing companies who are dealing with genotyping (determining differences in the genetic make-up of an individual and comparing it to another individual’s sequence), not whole genome sequencing. That you find at Human Longevity, Full Genomes, Sure Genomics or Veritas Genetics.
Are you curious whether your forefathers hunted deer in an Inuit tribe or sailed to New Guinea with the European conquerors? If the answer is yes, ancestry tests will fascinate you. However, you should keep in mind that in most cases the results are a mixture of all kinds of races and ethnicities. In the case of some American white supremacists, their intention to prove their racial superiority nastily backfired when they decided to go for a genetic test, and they did not like what they found. For all others out there, ancestry tests are the celebration of human diversity.
The three biggest DTC genetic companies, FamilyTreeDNA, Ancestry.com, and 23andme, will all help you map your unique family tree. With Ancestry DNA, you have the chance to upload your results for free and connect with matches at FTDNA.com, MyHeritage.com and free third-party sites like gedmatch.com and DNA.Land.
In my experience, National Geographic produced the ultimate guide to find out more about your genetic heritage. The analysis not only informs you about the races and ethnicity to which your ancestors belong, but it traces back your ancestry lineage for thousands of years, drawing up clear migratory paths where your forefathers lived and how they wandered around from one place to another. Moreover, you can participate in The Genographic Project; a multi-year, global genetic anthropology study that aims to map historical human migration patterns by collecting and analyzing DNA samples. As of 2017, over 830,000 participants in over 140 countries have joined the project. Just always be careful to send your sample to the right place…
2) General health risks
Many human diseases have a genetic component. Several DTC genetic testing companies offer to assess your risk of developing such conditions. They emphasize in every case that usually environmental elements have as much influence on the development of the disease as genetic factors.
23andme assesses your DNA for five different conditions, including Alzheimer’s disease, Celiac disease or Parkinson’s. The company stresses that their report is only for information, not a diagnosis. However, I couldn’t test and review it – simply because I’m not a citizen of the United States, so I couldn’t order a test to be shipped to Europe.
I recommend Futura Genetics if you want to know whether you have a health risk for genetic conditions. The Futura Genetics test is a non-invasive DNA test designed to assess your risk of developing each of the 28 most common conditions worldwide such as lung cancer, lupus, melanoma, migraine, Alzheimer’s disease, breast or bladder cancer. The team of their experts selects the most appropriate genetic markers for each disease, based on their experience.
A while ago, I also took the Navigenics test, which informed consumers as a health-related service about their risk for about 20 medical conditions, including diabetes, obesity, prostate cancer and glaucoma. In 2012, the company was acquired by Life Technologies which was bought by Thermo Fisher Scientific two years later.
Why do some people take two aspirins for a headache and have no problems, while others feel dizziness or even nausea? Without doubt, the response is that everyone’s genetic code and organism is different and metabolizes drugs in another way. Pharmacogenomics deals precisely with this issue area. It is defined as the study of variability in drug response due to the genetic code. It argues that despite general sentiments, medications do not have the same effect on people. There are already some who expressly recommend genetic testing before any prescription of, e.g. Warfarin, a type of anti-blood clotting drug takes place.
23andme’s genetic test offers you some insight into how your DNA relates to caffeine consumption, lactose digestion, and in some cases, it also includes drug response tests like abacavir hypersensitivity and warfarin sensitivity in their services.
If you want to learn about how your body responds to drugs and what potential side effects your organism shows for medication, I recommend you the MyDNA genetic test. It helps you and your doctor personalize your treatment by selecting the most appropriate drugs based on the test results. As a consequence, your physician could improve your health outcomes, reduce the risk of side effects and you could also save a significant amount of money by avoiding ineffective medications. It is especially important in case of common diseases and pharmaceuticals whose variations are widely available on the pharmaceutical market, e.g., antidepressants, antidiabetic drugs or pain medications.
4) Raw data analytics
Most companies offering genetic tests let users download their raw data. Although only genetic experts can analyze such complicated data sets, more and more services aim to help users do it themselves and thus learn on their own from their data. It does not substitute the professional analysis provided by DTC companies’ genetic counselors, but it can still be useful. Helpful tools, such as Promethease, GEDMatch, Genetic Genie, Oymygenes.com, Interpretome.com, Athletigen, Infino.me or Genomapp.com could tell you more about the raw genetic data in your hands.
My personal favorite, Promethease, is a literature retrieval system that builds a particular DNA report based on specific scientific literature to be found in SNPedia (a wiki investigating human genetics) and a file of genotype data. Customers of DNA testing services can use it to retrieve published data about their DNA completely independent of whichever company produced the data. You can upload your file from your computer, and the analysis will take only 15 minutes and cost $5. Finally, you will receive a personalized report with genealogical details to help you learn more about your ancestry and health information regarding your genetic risks for certain illnesses such as Alzheimer’s.
5) Are you a carrier of genetic conditions?
When you are a carrier of a disease that means you have a genetic variant for a condition. You will most probably not suffer from the illness itself, but you can pass that code to your children. The screening for carrier status is the most relevant in case of monogenic medical conditions, where the presence of only one pair of genes decides whether or not the disease will develop – environmental factors play no role whatsoever. DTC genetic testing could give users information about such conditions.
For example, Pathway Genomics screens patients for more than 120 recessive genetic diseases and offers a comprehensive preconception and prenatal package. 23andme tests consumers for example for cystic fibrosis, sickle cell anemia, hereditary hearing loss. Progenity’s regular preparental screening includes 29 disorders which may cause serious health effects in the future child. From these companies, I can recommend Pathway Genomics from my personal experience as it provided me with a comprehensive overview of my genetic heritage.
6) Specific genetic tests for certain conditions
The concept and practice of BRCA genetic testing became extremely popular after Hollywood actress Angelina Jolie publicized her results in 2013 alongside her decision to undergo a double mastectomy. If breast cancer or ovarian cancer is present in the family history, women are encouraged to take the BRCA test as one of the most popular genetic screening for a specific condition.
Together, BRCA1 and BRCA2 mutations account for about 20-25 percent of hereditary breast cancers; and about 5-10 percent of all breast cancers, which means a quite elevated risk. These numbers are even higher in the case of ovarian tumors: mutations in BRCA1 and BRCA2 account for 15 percent of that cancer type overall. Looking at prostate cancer cases, Prostate Cancer UK found that only 0.44 percent and 1.2 percent of such cases carry mutations in BRCA1 and BRCA2 respectively.
The most famous and oldest company for providing BRCA genetic testing is Myriad Genetics, but you might look up Ambry Genetics, GeneDx or Dante Labs. According to my review, the latter is the one that offers a thorough and scientifically sound analysis, but the results are not easy to interpret.
Not everything is coded in your genes
Genetics is not fortune telling or an astrology personality test: it cannot predict what your body mass index will look like in a couple of years, or which characteristics you have due to your genes. I am very suspicious with genetic tests which are claiming that you can find your love connection by taking their test, and I would most certainly dismiss anyone’s promise about telling me what talents my daughter will have based on one genetic screening. I can only recommend you the same. Be suspicious when it comes to genetics and DTC companies!
Genetics can most certainly provide you with valuable information regarding your health risks, your ancestry or drug response characteristics. However, it cannot be the ultimate guide when it comes to your personality traits, your sense of taste or your fate. I am not telling you not to order a DTC genetic test; I am just saying you should be careful in choosing the company, the test and you should be cautious when it comes to interpretation. Anyhow, if you have any doubts and questions, do not hesitate to reach out to your caregiver or genetic counselor.