Recently I wrote about the completion of the human genome sequencing project and the promise, problems and questions that the project has generated in the last decade and a half. One of the biggest realizations that I had from researching and writing that post is that our human genome makes us more alike than different at the molecular level, yet there is incredible variability in the human species around the globe.
I started to think about other things where the basic building blocks were the same, yet the final products were so very different—and I landed in the middle of a symphony orchestra.
Orchestras, if we look at the instruments that they have at their disposal, are very similar: dare I say 99% identical? For instance the instruments listed in the February 2017 roster for the New York Philharmonic Orchestra on Wikipedia (1) are very similar to the lists of instruments listed for the musicians of the Atlanta Symphony Orchestra on its web site (2). Numbers and groupings might vary, but the instruments are the same.
However no one would argue that the New York Philharmonic Orchestra and the Atlanta Symphony Orchestra and Chorus are interchangeable. Experiencing one is not the same as experiencing the other, and two separate experiences of either are often completely different.
There are 3 billion (3,000,000,000) bases in my genome—in each of the cells of my body. Likewise, Johanna, the writer who sits next to me at work also has 3 billion bases in her genome. Furthermore, our genomes are 99% the same. Still, that’s a lot of places where my genome can differ from hers, certainly enough to distinguish her DNA from mine if we were both suspected of stealing cookies from the cookie jar. The power of discrimination is what makes genetic identity using DNA markers such a powerful crime solving tool.
The completion of the human genome project in 2003 ushered in a tremendously fast-paced era of genomics research and technology. Just like computers shrank from expensive, building-filling mainframes to powerful hand-held devices we now call mobile phones, genome sequencing has progressed from floor-to-ceiling capillary electrophoresis units filling an entire building to bench top sequencers sitting in a corner of a lab. The $99 genome is a reality, and it’s in the hands of every consumer willing to spit into a tube.
Commercial DNA sequencing services are promising everything from revealing your true ancestry to determining your likelihood to develop dementia or various cancers. Is this progress and promise or is it something more sinister?