Genetic Sequencing May Not Be Ready To Become Routine
Originally published on Tue March 11, 2014 5:51 pm
ROBERT SIEGEL, HOST:
This is ALL THINGS CONSIDERED from NPR News. I'm Robert Siegel.
MELISSA BLOCK, HOST:
And I'm Melissa Block.
Getting your entire genetic code deciphered is the cutting edge of medicine. The test to spell out every letter in one's genetic blueprint can be done quickly and has become relatively inexpensive. That's raising the question: Is the technology ready for primetime? NPR's Rob Stein joins us now to talk about one of the first carefully done studies aimed at answering that question. And, Rob, why don't you back up first and explain just what it means to decipher somebody's entire genetic code?
ROB STEIN, BYLINE: Yeah, Melissa. As we know, our genetic code is what makes us who we are. It's made up of more than 3 billion chemical letters that carry the coding for more than 20,000 genes. The first time anyone deciphered the entire genetic code, it took nearly decades - hundreds of scientists working for nearly a decade and cost about $3 billion. Today, it can be done in just days, and it can cost as little as about $5,000. So some doctors have started to use this in medicine, and some are recommending that maybe we should do it on everybody as part of routine medical care.
BLOCK: Some are recommending that, but not all. This is a controversial idea, right?
STEIN: That's right. That's right. Some say, look, this is the future of medicine, the future of what we call personalized medicine. You could produce lots of really valuable information about whether we're at risk for certain diseases, what drugs work best for us, what we should eat. But others say, look, right now, it would just produce a flood of confusing, vague information that would end up scaring people unnecessarily and then forcing them to get all sorts of tests and procedures. It could end up being expensive and do more harm than good.
BLOCK: And that was the idea behind this study that I mentioned, trying to figure out the reality here. Tell us about the study, how it worked, and what they found.
STEIN: Right. This group at Stanford, they've decided to sequence 12 healthy people using two different methods that basically see how well it would work and what they'd find out and how much it would cost. And what they found was that on the positive side, you know, it did produce some very useful information. It determined that some of the people were at risk for certain diseases like diabetes and heart disease. One woman even found out that she was at high risk for ovarian cancer and breast cancer and was able to take some steps to protect herself.
On the negative side, the researchers determined that the two different versions that they used produced very different results and conflicting information, which is a really big red flag that indicated that often this testing will produce a lot of incorrect information that would scare people unnecessarily and also reassure them in ways that wasn't true. Also, it ended up costing about $17,000 once you added up all the costs of the testing, the analysis, the follow-up exams. And it took an enormous amount of time - about 100 hours for each patient.
BLOCK: Is that cost ever covered by health insurance?
STEIN: You know, right now, it generally isn't. It's only covered in very specific situations where somebody is using it for a specific medical purpose, like for somebody who has a mysterious condition that nobody can diagnose, or for a cancer patient perhaps, trying to figure out if there's a better drug they should take.
BLOCK: Mm-hmm. Well, in the end, Rob, where does this leave things? Does whole genome sequencing have a place in medicine or anytime soon? Or is that still quite a ways down the road?
STEIN: You know, the current thinking, I think, among most experts is that, yes, it's clearly very exciting technology that will play a very important role in medicine and for those specific patients that I mentioned, people who have a specific reason to have it done, like a cancer patient looking for a better drug, or somebody who's on what they call a diagnostic odyssey where nobody can figure out what's wrong with them.
For them, it can be very useful. But a lot of people think, you know, we're not quite there yet. We have to get a lot better at doing the analysis and doing the sequencing and really knowing whether it will have useful information for most people.
BLOCK: So the idea of going in to your doctor, getting a flu shot and, oh, by the way, do you want to get your genome sequenced, no time soon.
STEIN: Yeah. Well, you know, it can be done right now. You can sign up and get what's called getting your exome sequence, which is not your entire genome but all the genes that we know about. And some people are doing this. But most people, I think, would say right now that for the general population, we still got a ways to go before it becomes routine.
BLOCK: OK. NPR's Rob Stein. Rob, thanks so much.
STEIN: Oh, thanks for having me, Melissa. Transcript provided by NPR, Copyright NPR.