Before the current popularity of looking for your ancestors through websites that offer DNA testing, there was a large scientific undertaking called the Human Genome Project. It started in the mid 90s and wrapped up in 2003. It was controversial in some communities because people feared it was an effort to steal their genetic information, or worse, create bio targeted weapons.
Dr. Eric Green, Director of the National Human Genome Research Institute at the National Institutes of Health, says those fears were unfounded. He says the project’s signature accomplishment was reading out the three billion letters that make up the human genome sequence. Dr Green gave the keynote address at a Southcentral Foundation conference in Anchorage last week.
He spoke with Alaska Public Media’s Lori Townsend and said the sequencing was successfully completed in 2003, but he says that was really just the start of understanding the blueprint of human DNA:
GREEN: We’re interested in each of our genome sequences and in particular we’re interested in how we differ. It turns out that if we lined up our genome sequences we differ about one out of a thousand letters — we’re 99.9 percent identical. We are very different in many things about our health, our well-being, features, etc. And so, it’s all of those differences, or most of those differences are coded in that .1 percent of the letters that are different between it. And so the real interest is not so much how are we the same. The real interest is how are we different. In particular, I can tell you as a physician, and particular working at the National Institutes of Health with a health focus, we’re particularly interested in which are the differences amongst peoples’ genomes that play a role in their health and influence on human disease.
TOWNSEND: So talk a little bit about that. What was learned or what is still being learned from this undertaking, and how does it help in the understanding of disease?
GREEN: So the journey to understand the human genome began 15 years ago when we had in front of us the first sequence. That journey is far from complete by any means, but we’ve made a lot of progress in 15 years. Most importantly we’ve gotten extremely good at being able to read out genomes now much more cost effectively. I’ll give you some numbers. That first human genome sequence generated by the Human Genome Project cause something like a billion dollars. Now the cost for sequencing the human genome is down to just a little over a thousand dollars. It’s a million fold reduction. What that has allowed us to do is to go out and sequence literally hundreds of thousands of people’s genomes and catalog all the differences.
TOWNSEND: And is it, at its most basic, the trying to better understand what — I guess normal human biology is probably inadequate — but just a deeper understanding of individual biology?
GREEN: That’s absolutely right. You know, when genomics is being used in research to understand disease, it’s giving us brilliant insights about what’s broken when you have a patient with hypertension what’s broken in the pathways that lead to diabetes, but when we talk about genomic medicine, that’s that’s not just biological knowledge that’s knowledge about an individual. So much of our differential drug response is scripted in our genomes in subtle spelling differences in what turned out to be the pathways that metabolize drugs. And so either, it’s there’s certain medications that you’re better or worse to take or at least the dosage might be higher or lower depending. So there’s a big word for this pharmacogenomics. It’s just pharmacology and genomics. It is not making new medicines for each patient, but rather picking the best medication off of a list of possible medications and using that or adjusting the dose based on that. That’s not hypothetical that’s here and now for a handful of medications. I predict that list will grow because we’re learning more and more every day about the genomic variants that influence drug metabolism and how that influences the best choice of medications that’s here and now.
TOWNSEND: I’m so glad you raised that because I wanted to ask a question about a friend of mine who is going through treatment for cancer and has transitioned from chemo and radiation to immunotherapy. Is that part of what you’re talking about? Is immunotherapy informed by genomics.
GREEN: It can be informed by genomics. Immunotherapy is slightly different in that it’s basically harnessing your body’s natural immune tools to basically go out to cancer and there’s some spectacular exciting advances. But if you take a step back from that, what we’re starting to use genomics for is to take each patient’s individual cancer and instead of just trial and error will try this and we’ll try this, what we’re hoping will come out of it, by doing genomic studies of that tumor, from that patient, better knowing upfront, based on the unique genomic changes that have taken place, whether this therapeutic option or that therapeutic option is the most effective way to go.
TOWNSEND: Dr. Green, you’re giving the keynote address at the annual Southcentral Foundation’s conference on the NUKA system of care. What do you plan to focus on in in your talk?
GREEN: So I think the overarching goal of my talk is to really just describe this journey, and actually it’s plural it’s journeys. It’s my professional Journey that as I was just laying out of sort of going from a freshly-minted physician scientist, and then training in pathology and then having this ability to walk down this path of genomics, which is turned out to be a remarkable remarkable adventure. But then the journey of genomics and seeing it go from something that once upon a time had some skepticism around it, to now, in a very short period of time, delivering on its first major promise: the Human Genome Project. And now having the herculean task of trying to change something as complicated as medical care.