BACK in 2002, before the $3 billion Human Genome Project was even complete, some biologists began to talk of sequencing the entire genome of any individual for just $1000. While DNA sequencing is getting ever cheaper and faster, we are not quite there yet: about a tenth of the human genome remains impossible to sequence with existing methods.
Nevertheless, the age of the personal genome seems to have snuck up on us. Three companies are now offering extensive DNA read-outs directly to the public. First off the blocks, in November last year, was Google-backed 23andMe, followed closely by Iceland’s deCodeMe, both charging about $1000. This April, Silicon Valley-based Navigenics offered a package with a price tag of $2500 and a yearly fee of $250. For that you get access to “genetic counsellors”, and the company will also freeze and store your DNA to re-analyse as the technology improves.
All three companies use DNA chips to read off hundreds of thousands of the most common single-letter variations in people’s DNA, known as single nucleotide polymorphisms (SNPs). While this does not provide nearly as much information as sequencing the entire genome, these scans do offer people an unprecedented glimpse of their own genetic blueprint.
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The real challenge, though, is not reading the genetic information but interpreting it. As yet, we don’t have a clue what, if anything, most SNPs mean for those who possess them. Some SNPs have been statistically linked to the chances of having certain traits or developing particular diseases, but such associations could be misleading because the effect of many SNPs could be very different depending on what other genetic variations you possess, or on environmental factors, or both. For instance, one SNP has been linked to higher IQ – but only if you were breastfed as a baby. SNPs with a clear and simple consequence – such as – are likely to be the exception rather than the rule.
Given these limitations, is it really worth having one of these SNP scans? Are the results life-changing? A passing bit of fun? A first step on the road to better health and happiness? To find out, New Scientist asked six people who have done it.
Terry Drotos, 53, IT analyst and instructor, Redwood City, California
I wanted a genome scan largely because I am adopted. I’ve always been concerned about not being able to give my daughter any family history from my side, and I got into the beta-testing group for Navigenics because my brother-in-law did some work for the company.
As far as my results went, there was nothing really awful, which was great news. I was lower than the average for Alzheimer’s disease and I was very, very thankful for that. My mother – not my biological mother, but the mother who raised me – is 92 and in the late stages of Alzheimer’s, and watching what is happening to her is the most horrible thing.
What’s interesting is that where I do have a higher risk, you wouldn’t be able to guess it by looking at me, which is the whole point. I have a higher than average risk for type 2 diabetes, obesity and also for osteoarthritis. It does make me realise that if I didn’t exercise and eat well and take care of myself, I would probably have some health issues by now.
The other really interesting thing is that my daughter was starting to struggle with her weight and blood pressure around the time of my test. I was keeping my mouth shut because I didn’t want to make it an issue. But when she saw the results of my genome scan, she said “Oh my goodness.” I can’t tell you how she has totally turned around. She’s lost about 20 pounds since Christmas. It really did motivate her. That to me is, out of everything, just the best.
“If your doctor knew that you were going to die in a month, would you want to be told?”
Sure, the overall advice that Navigenics gives you is to eat right, exercise and stop smoking, but this is merely the beginning. It will lead to medications that are geared more towards one’s genetic make-up. Take my mother. She has been on so many different drugs for Alzheimer’s, and some of them she did really poorly on. If a genetic test like this could have determined that she doesn’t have a certain enzyme that makes a drug work, or not work, that would have saved her a lot of misery.
It’s sort of like if your doctor knew you were going to die in a month, would you want him to tell you or not? To me, of course I would. I want that control. Being adopted and never to be able to find out anything has been so degrading for me. I kind of feel like now I have something. I have something that nobody can ever take away from me.
Mark Fletcher, 37, Internet entrepreneur, Redwood City, California
I wanted to have my genome scanned to see what I could learn about my chances of getting Alzheimer’s disease, because two of my grandparents had it.
I told my parents that I was doing it, and they forbade me from telling them anything I found regarding Alzheimer’s. I was a little surprised by their reaction, but I am not in their shoes. They are much are closer to the time when the disease would manifest.
At the time I did it, 23andMe were providing reports on 20 or so different conditions and traits. That was interesting, but it was also a little disappointing in that it wasn’t terribly useful. For example, I have a slightly higher chance of getting type 2 diabetes and a slightly lower chance of getting type 1. But we’re only talking about very small deviations from the average. I was a little underwhelmed.
Then I went into the raw SNP data where I was hoping to find out more about my Alzheimer’s risk, because 23andMe didn’t offer a full report on it. The raw data is the core of the service, but they give you no additional information to interpret it. I started looking around the internet and came across , which is basically a wiki for SNPs and their associations.
“I told my parents I was doing it and they forbade me from telling them anything”
I found a handful of SNPs that are correlated with Alzheimer’s. But the SNP with the strongest association is not among the 600,000 SNPs that 23andMe genotypes. The ones I was able to look up showed that I am not predisposed to early-onset Alzheimer’s. That’s nice, but not unexpected because it wasn’t early-onset in my relatives.
I was a little disappointed overall, but I think I was also realistic. I had an inkling that the science was very preliminary. I would have still done this knowing what I know now, just because I like geeking out on the science aspect of it. When sequencing your full genome becomes affordable I will do that, too.
Robert Green, 53, Medical researcher, Boston, Massachusetts
I gave some informal unpaid advice to both Navigenics and 23andMe. Navigenics asked me to be a beta tester and 23andMe offered me complimentary testing. I was curious to see my results, of course, but I was also curious to see the differences between the two companies.
Navigenics requires you to “opt in” to each condition, which is good if you want to know about one thing and not another. I saw the Alzheimer’s disease box and I knew it was an SNP that reflected the ApoE gene. I went ahead and checked it. That was an interesting moment, because I have been studying ApoE and Alzheimer’s disease at Boston University for nearly 10 years and have had many opportunities to order my own test but never did. I guess I didn’t want to confront it if it was positive. According to Navigenics, I have a lower than average risk of developing Alzheimer’s. That was a relief.
Another thing I was eager to see was the reports on cardiac genes. I had coronary artery disease and a triple bypass at 52, which is unusual since I don’t smoke, am not overweight, I exercise and my cholesterol is normal – which means it has to be genetic. But neither service found my risk of heart disease to be meaningfully different from average.
Some of my other results also illustrate difficulties with these services. For example, my multiple sclerosis box in Navigenics was highlighted orange, which means my risk is more than 20 per cent above average. But the average risk was given as 0.3 per cent and my risk was 0.5 per cent. Those are very, very low risks, and yet the box was coloured orange because of their algorithm.
I agree with some of the critics who say that the modest effect sizes being reported are difficult for an individual to interpret meaningfully. The average risk of type 2 diabetes is 25 per cent and mine is 19 per cent. I know that my family history and my body mass index are far more important in determining that risk than these susceptibility genes. So they are giving only a partial message that might even be misleading.
“Susceptibility genes give only a partial message that might even be misleading”
Both companies explain very thoughtfully that you must take the results in context, and what your risk depends on aside from genetics. The question is how much of this do people read and how much do they assume just by glancing at their results?
I think we really have to make a big distinction between this kind of personal genomics and the questionable genomics where people are doing nutrition or matchmaking based on genetics. That is very different. We can all debate the value of the information given by Navigenics and 23andMe, but they are legitimately running these scans and they are trying to interpret them fairly. I think it’s wonderful that they are trying to do it responsibly.
Ultimately, I was prepared to take my results with a grain of salt; the science is still so imprecise. But when we get more genes that really define the risk of a particular disease, these guys are going to be way ahead of the curve on providing that information. They are just on the cutting edge.
Perry Pickert, 32, Video producer, San Francisco
I was in the beta-testing group for Navigenics because I went to high school with someone who works for the company, so I got the service for free. But for me it would have been worth the $2500 anyway. I am not saying I would have done it that week, but I would have eventually, for sure.
My results were all pretty good. My grandfather died of prostate cancer and my father had colon cancer, so I thought I would be pretty high on those two, but I was about 30 per cent less than average for both. I was ecstatic. My highest risk by far was for restless legs syndrome. I’d never heard of it before. At first I thought one of my friends had played a joke on me and made up a fake syndrome. I also had a higher chance of macular degeneration, which is a little unnerving. I went out and bought sunglasses.
“My highest risk was for restless legs syndrome. I thought it was a joke!”
The biggest thing for me was just putting in place a way to manage my health. I had no plan. I have no primary physician and I only seek medical attention if I am literally crippled. I just hate going, it is so dehumanising. Every time I step through the door I end up paying a crapload of money and not getting anything out of it. I only see the doctor for about 6 minutes and I have to understand what they are saying and then instantly come up with brilliant questions so I can get the information I need. I leave frustrated and without any understanding. I’ve had some really dreadful experiences.
For example, in my last year of university I got injured. The doctors said they were sure I had torn my anterior cruciate ligament. The surgery is awful, and it would have been a year of rehab. I was freaked out. Then I went and did all this research online. I realised the method they were using to diagnose me wasn’t very accurate. I was like “you have to show me my torn ACL before you start breaking stuff”. And sure enough, I just had a torn meniscus, which is really small.
That second opinion was the only good experience I’ve ever had because I knew what I was talking about. I came to the appointment empowered rather than totally helpless. That’s the doctor-patient relationship as it currently is. They have all the information and control.
That is what I am so psyched about the Navigenics information. I think it will give me the foundation so that when I go in there I will feel like I can get my head around things.
It’s like you’ve taken at least one Italian class when you show up in Italy – so you know how to say, “Hello, where’s the bathroom,” and “How much is that?” Then it’s easier to learn and put all the rest of the information in context. For me, it’s just perfect.
Lara Sasken, 31, Account manager, San Francisco
My brother-in-law is a director at Illumina. They make the chip that reads the DNA results for 23andMe. He was offered a friends-and-family deal for $250 per person, so my whole family decided to do it.
I just figured it was an interesting thing to do. Why not? My mom was worried about privacy issues. In the future there might be , and these days so much information is public on the internet, who knows who could access it? 23andme is sort of like the Facebook of genotyping because you can share your profiles. So there were some concerns, but we all decided to do it so we could all compare chromosomes.
When I got the email saying my results were ready I was all of a sudden really nervous. When you log in they give you all these disclaimers: are you sure you want to see this?
But as I started going through the results it just became fun because there was nothing bad in there. I had been most nervous to see the results for diseases like heart attack and breast cancer. It turned out that my odds were lower than average for all of these things.
“My family all decided to do it so we could all compare chromosomes”
I don’t know what I would have done if it had been the other way around. I guess it would have caused me to worry a lot, sure. You can be healthy, you can not smoke, you can live in an area that’s not polluted, but you can’t do anything about your genes. That is another reason why the experience is really intense. You think you are doing everything right, then you can log in and see that it doesn’t matter. And that’s kind of scary.
When I got my results in January there were only about 20 conditions reported on; now it’s 60. And some of the new ones are kind of ridiculous. They added one called “avoidance of errors” which basically tells you if you have a gene that makes you good or not so good at making mistakes. What does that mean?
Frankly, I am just not interested in it any more. I just don’t know enough about genetics to make sense of all of it. So at this point, I wouldn’t recommend it. It’s not worth $1000.
Of course, there’s a lot more to find out. If the company stays around, in five years you might be able to tell a lot more.
Jay Cross, 63, Business author and change agent, Berkeley, California
When I read about 23andMe, I was intrigued. Might a genome scan tell me something useful about my health? Would it provide any insight into whether my heart attacks were the result of nurture or nature?
Getting involved is harmless. Just spitting in this little tube that gets mailed off to Palo Alto for analysis.
At the moment, I don’t think this is going to have much impact on my healthcare. My results turned up nothing extreme. I’ll alert my optometrist to be on the lookout for macular degeneration. My SNPs showed that I am 30 per cent more likely than average to have restless leg syndrome, so it confirmed something I already knew. It also told me that my eyes are blue. Well, yeah, I’ve got a mirror. And surprisingly, I was 20 per cent less likely to have heart disease.
“It’s part of a longer journey. It’s not an immediate payback thing”
There’s a lesson in this – it ain’t just genes. You’ve got a nice mix of all kinds of genes, plus environment, plus a lot of esoteric experiences. It’s impossible to figure out what came from where, so the genome scan doesn’t provide the satisfaction of a definitive test with crisp results. If 23andMe had found some condition where the genetic component was 80 per cent and my marker predicted a 90 per cent risk, I would be in my car immediately. We just didn’t find any of those.
So have I gotten enough out of it to justify paying for it, aside for entertainment? Probably not. If I had the money to do it again, would I spend 999 bucks for this? I think I would. It’s part of a longer journey. It’s not an immediate payback thing. I enjoy the possibly of learning more.
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