I just listened to this little story on NPR about biochemists at Scripps Research Institute in La Jolla, California (across the street from my high school!!) who are attempting to create two new synthetic bases for DNA. Honestly, my gut reaction is that this is kind of a biochemical blasphemy, haha. They say, ‘just imagine what we could do with infinitely more genetic code combinations, and imagine being able to code for so many infinitely more things in our bodies’. This actually kind of scared me. I feel like the system we have now is what we have because it functions so seamlessly together (demonstrated by all these presentations we’ve been having too) and is incredibly efficient and diverse despite having only 4 bases. So many more changes would have to be made for us to even process these new bases. DNA polymerase, DNA’s shape, enzymes that repair DNA, RNA polymerase, RNA bases, size of histones, size of chromosomes, transcription factors – all of these and infinitely more tools for processing out genetic code in the cell would have to be changed. Not to mention if our cells mess up while reading these new bases with these new tools, cancer would quickly become an even larger problem. Not sure how I feel about it!
http://www.npr.org/blogs/health/2014/05/07/310282870/chemists-expand-natures-genetic-alphabet
Wait, also what else exactly do they want to synthesize by creating new bases? Why not use what we also have? Also, how exactly are they imagining incorporating these new base pairs? Are they suggesting cutting out certain “unused” DNA sequences and inserting their new ones? Or do they want to add them in?
As we learned in Nucleic Acid Group A’s presentation, DNA is long! How are you going to add entire new coding sections?? Where would you put all that?
It seriously raises the question of scientific ethics – are we willing to create a new type of person?
This is interesting! and something I didn’t think about until now, but now that I think about it, I’m not so surprised people are trying to reinvent the DNA composition. Its on the same level of cloning and other scientific knowledge used to manipulate the natural process of life (not that I’m particularly against or for this. I just seeing it becoming more and more prevalent in the future.)
There’s one caveat. If they’re just trying to incorporate these new bases into nucleic acids in the lab by synthesizing the nucleic acid chains themselves, that’s one thing. But if they’re looking to have these bases become part of the genetic material, which is self-replicating (without outside help,) polymerases would have to recognize these bases. And then the complements of these bases would have to be stable. It would be interesting whether more amino acids are possible based on more diverse codons. However the reason we have only 20 amino acids is that is what evolution afforded us. These were the amino acids needed by our body. The chemistry we currently have in our bodies was enough for this. Introducing more bases, which were once possibly naturally occurring, but are no longer because they weren’t needed, would probably not have an impact. or maybe they would….