Category Archives: Biology

Four New Synthetic Base Pairs Added to DNA

All life on earth uses DNA with four types of base molecules arranged in a “double helix” to encode information as sequences of Adenine-Thymine (A-T) and Cytosine-Guanine (C-G) pairs. Because A pairs only with T and C only pairs with G, DNA can be split into two halves and then each half may be completed so that two double helices with the same information can be obtained. Nature also uses the “genetic code” to translate the information in DNA into specific amino acids via its molecular machinery that assembles proteins in the correct sequence.

Now scientists have doubled the number of base pairs of DNA by adding four synthetic ones to the original four natural ones. Four new base molecules S (a Pseudo-T), B (a Pseudo-B), Z (a Pseudo-C), and P (a Pseudo-G) have been created so that S only pairs with B and Z pairs only with P. Now you have twice as many options as you had before and so this “hachimoji” (eight letter) DNA can have much greater information density. Plus if you re-engineer the molecular machinery to use these new bases you can have a brand new extended genetic code to build all sorts of synthetic proteins.

Further Reading:

https://www.scientificamerican.com/article/four-new-dna-letters-double-lifes-alphabet/

http://science.sciencemag.org/content/363/6429/884

https://gizmodo.com/freaky-eight-letter-dna-could-be-the-stuff-aliens-are-m-1832823430

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The Brain with David Eagleman

sq_whowhatSpeaking of brains, “The Brain with David Eagleman” by neuroscientist and author David Eagleman is currently showing on PBS. The first episode “What is reality?” was pretty good, showing reasons why what we think of as an objective reality is really just a temporally delayed and conceptually constructed neurological fabrication.

The six episodes are titled:

  1. What is reality?
  2. What makes me?
  3. Who is in control?
  4. How do I decide?
  5. Why do I need you?
  6. Who will we be?

I wonder if the answers to these questions will pretty much be “the brain, the brain, the brain…”. Check your local listings and tune in to find out!

Books:

David Eagleman / The Brain: the story of you

David Eagleman / Incognito: the secret lives of the brain

David Eagleman / Sum: forty tales from the afterlife

David Eagleman / Why the Net Matters: six easy ways to avert the collapse of civilization

References:

Home

https://en.wikipedia.org/wiki/David_Eagleman

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