Scammed? How to find out whether a DNA test is reliable

In this article we report on a small investigation we carried out ourselves into the ‘DNA-Healthtest’ from the provider 123Healthy, supplemented with findings from the TV programme Opgelicht?! We also set out a number of questions with which you can find out for yourself whether a provider is reliable or (probably) not.

Occasion: a DNA test for just 35 euros

As one of the best-known providers in the Netherlands, we naturally keep a close eye on the DNA test market. And some time ago we came across the ‘DNA-Healthtest’ from 123Healthy. Via Groupon this test cost just 35 euros(!)

Since we know what it costs to carry out a decent DNA test, we wondered how 123Healthy could offer such a test for this money. To put it to the test, our colleague Marike ordered a test herself…

Investigating…

Before going ahead with the purchase, Marike asked by email whether she could get the raw data (after the test). That turned out not to be the case. The answer was: ‘We only provide the report as stated in the offer.’

She also requested a demo report. In several places in this report she checked the scientific references. Her findings: “The good news was that the studies were roughly about the right subject. The bad news was that they regularly involved a small, irrelevant study population. In short, not at all sufficient as substantiation.”

Results based on a sample without DNA

In the end Marike did buy a kit via Groupon. But because she did not trust the set-up, she sent in a ‘sample’ that contained no DNA. “I wanted to see what would happen if there was insufficient DNA for a determination.”

Well, on 11 January Marike received a message that her DNA sample had been received, on 16 January that the DNA sample had been sent to the laboratory, and on 19 January that the DNA analysis was being started. Then on 31 January the health report arrived.

“I found that remarkable, because I had not supplied any DNA. Moreover, the report was written in poor Dutch. So it was also insufficiently substantiated with scientific studies and was indeed supplied without underlying raw data. When I asked by email whether I could still get my raw data, the answer was: all raw data is destroyed immediately after the report is sent.”

DNA-Healthtest in Opgelicht?! our suspicions confirmed

We were apparently not the only ones who found the ‘DNA-Healthtest’ suspicious, because on 12 February this test was discussed at length in the AVROTROS programme Opgelicht?! Our suspicions were confirmed.

The broadcast shows how two different customers receive reports that are very similar. When they have their DNA ‘tested’ again, the new results turn out to differ enormously from their earlier results. This sets alarm bells ringing. When sending in a dog’s saliva then produces a report in which the dog is advised to follow a Mediterranean diet, the programme contacts the founder of the company.

Associate professor of Biomedical Genetics Marc van Mil also speaks in the broadcast. And we have to admit: we do not always see eye to eye with him when it comes to the added value of DNA self-tests. But where it concerns defective DNA tests we wholeheartedly agree with Marc: this kind of quackery is highly objectionable.

How do you check whether a DNA test is reliable?

That the DNA-Healthtest is a dubious provider should be clear after the broadcast of Opgelicht?! But how can you find out whether you are dealing with a reliable party?

In the form of a checklist beforehand and a checklist afterwards, we set out a few things with which you can find this out yourself. Because both before and after taking a DNA test there are all kinds of signals you can look out for.

• Checklist beforehand: is a DNA test reliable or not? Is the DNA test very cheap? Do you receive clear information about the procedure and do you know what happens to your DNA data? Can you view a sample report? Can you request the raw data? On what scientific research are the results based? Is personal contact possible? Is the offer too good to be true?

More about DNA tests

1. Is the DNA test very cheap?

Analysing DNA has become steadily cheaper over the years. But laboratory costs still make up an important part of the costs that parties charge for a DNA test.

Does a DNA test cost less than €100? Such a low price can indicate that less information is provided, that savings are made on lab costs, or that no laboratory analysis takes place at all. A cheap test can also be a reason to check what the provider’s revenue model is: selling DNA kits or reselling your data?

2. Do you receive clear information about the procedure and do you know what happens to your DNA data?

The website of every provider should clearly state what happens to your data and your DNA sample. Because your DNA is personal, privacy-sensitive information, of which you always remain the owner yourself.

Does a provider leave even the slightest possibility open that your DNA data can be resold to third parties? This can be a signal that another party has more to gain from the analysis of your DNA than you do.

Pay extra close attention to this if the price of a DNA test is below €100. The lower the selling price, the greater the chance that a provider has an additional revenue model.

3. Can you view a sample report?

Reliable providers often have a sample report on their website. We ourselves offer, for example, a free DNA test demo. It is not based on your DNA, but you do see how results are presented, so that you know what you are buying.

In a sample report you can usually also find more information about the scientific substantiation of the test results. Do you see, for example, that statements about a complex subject are already made on the basis of a single SNP? Then the information you receive may be less reliable.

4. Can you request the raw data?

During a DNA analysis, hundreds of thousands of SNPs are often mapped. From the point of view of relevance, however, usually only a few dozen SNPs are named directly in the test result.

Is it a reliable test? Then you must also be able to request the information about all the other (possibly less relevant) SNPs from the provider in question. In fact: because it concerns your personal data, you as a customer are always entitled to it.

5. On what scientific research are the results based?

A great deal of scientific research has already been done on the relationship between DNA and all kinds of conditions on the one hand, and the influence of nutrition and lifestyle on the other. But note: studies sometimes contradict each other.

A reliable provider therefore bases the results presented not only on individual scientific studies, but also on so-called meta-analyses, in which several studies on a particular subject have been included.

Does a provider substantiate the results of your DNA test only with individual studies, with little research or even with no scientific research at all? Then you are probably dealing with a less reliable company.

6. Is personal contact possible?

Do you get answers to the questions you ask by email? Or better still: can the company be reached by telephone or via chat?

7. Is the offer too good to be true?

It is common folk wisdom. Does something seem too good to be true? Then it usually is. This applies not only to improbably low prices, but also to unbelievably attractive product promises.

For example, the DNA-Healthtest newsletter claimed that a low-carbohydrate diet can cure Alzheimer’s. Stichting Alzheimer Nederland, however, distances itself from claims of this kind.

• Checklist afterwards: are the results of your DNA test reliable? Do your results look very much like someone else’s? Do the results differ greatly from those of a first-degree relative? Do you get different results if you take the test again? Does certain information not tally with what you know about yourself?

1. Do your results look very much like someone else’s?

Do you know someone who has taken the same DNA test? And did you receive (almost) exactly the same result or advice? Then two things may be going on.

Either only a few different SNPs have been mapped, so that the advice is based on a limited amount of genetic information. Or there is a standard set-up and no DNA analysis has been done at all (this seemed to be the case in the broadcast of Opgelicht?!).

2. Do the results differ greatly from those of a first-degree relative?

Suppose both your parents have taken the same DNA test as you. Then you can expect your results to match those of each of your parents for about half.

With brothers and sisters it is theoretically possible that their results differ more strongly from yours. But on average, about half of their mapped SNPs will also genetically match yours.

3. Do you get different results if you take the test again?

Have alarm bells gone off for you? Or have you chosen for another reason to take a certain test again? And does the second result differ strongly from the first?

Then two things may be going on. Either a laboratory error, or an unreliable test.

4. Does certain information not tally with what you know about yourself?

You inherit your DNA from your parents. With a health test that focuses on your predisposition to certain conditions, your risk of certain conditions will therefore often have similarities with conditions that occur in your family.

This does not necessarily have to be the case, incidentally. But if a test also gets things wrong on matters such as your sex, the colour of your eyes, your hair colour or your lactose sensitivity, then you can really question the reliability of the test results.

Finally: a quality mark for DNA tests?

We understand that you do not simply have several tests done by one provider, just to check whether the results might differ. Nor will everyone want to study all the scientific sources to find out whether a test is reliable.

We therefore argue instead for a national (or European) quality mark. With it, consumers should be able to see at a glance whether they can regard an online DNA test as reliable.