When you think about how the genome works, that is thinking about how it works commonly for all of us. But the other big emphasis in genomics—especially in the last 10 years—is to understand how our genomes are different. So there you can emphasize the 0.1 percent of our genomes that are different compared to one another and how do those differences lead to different biological processes. So there, understanding variation is very, very important, and then correlating that variation to different consequences, of which disease is a major part of it.
There have been remarkable, just truly remarkable advances. We now know the genomic basis for almost 5,000 rare genetic diseases. When the genome project began, there were only a few dozen diseases for which we understood what the mutation was causing that disease. That is a huge difference. We now know many, many hundreds and hundreds of regions of the human genome that contain variants—we don’t know which variants yet—that are conferring risk for more complicated genetic diseases, like hypertension and diabetes and asthma, cardiovascular disease and so forth.
We have gone from having a complete lack of knowledge of where to look in the genome for those variants to now having very discrete regions to look in. So this is a big emphasis now in genomics, is trying to understand which variants are relevant to disease and what to do about them.