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Design

CRISPR (Clustered Regularly Interspaced Palindromic Repeats)

If the terms programmable, firewall and edits make you think of computers, then this is not a surprise, but the connection to tiny living cells may be unexpected. Within the last few years, scientists have discovered that some tiny microbes display a system which eliminates potential hostile invasions into the cell.

Computer virus attacks come in the form of strings of computer code which will have a negative effect on any computer that they invade. A firewall is a computer program used to identify and eliminate incoming computer viruses. Within the last few years, scientists have discovered that some tiny microbes (very tiny cells which lack a defined nucleus but still have DNA) also have a system which eliminates potential hostile invasions into the cell. These tiny bacteria (like E. coli in your digestive system) are able to identify and destroy incoming hostile DNA (from real viruses).

The bacterial firewall works like this. Programmed into the DNA of the bacterium is a short unusual order of nucleotides called a CRISPR sequence. Attached to this is a short piece of DNA which was snipped out of a previous invader and attached to the CRISPR. The CRISPR and attached short hostile specimen are duplicated into RNA. Together this combination roams the cell looking for entire strings of DNA which include the specimen snippet. When they find one, they attach to the foreign DNA. In response, along come some specialized proteins (the big guns!!) which chop up the foreign DNA. There can be many different CRISPR-foreign snippet combinations in the cell looking for hostile invaders.

Scientists have discovered that they can program other snippets of DNA (of the scientists’ choice) into a CRISPR system. They can now precisely cut DNA at any location they desire. Also, they can tamper with the associated proteins to produce all sorts of fancy effects never before possible. See for example germ line changes and gene drive mutations.

The CRISPR system is clear evidence that life is designed:

  1. Like computers which are programmed by intelligent agents, so the CRISPR system could only have been developed by amazing intelligence.See Jennifer Doudna (winner of the Nobel Prize for CRISPR discovery): “CRISPR, we were beginning to understand, was far more complex than anyone had imagined possible for simple, single-celled organisms. In some respects, the discovery of this part of the bacterial immune system placed bacteria on an equal footing with humans by showing that we both have incredibly complex cellular reactions to infection.” [Doudna and Samuel Sternberg. 2017. A Crack in Creation. The Bodley Head, London pp. 281. See p. 59.]
  2. Amazing as the CRISPR system is for identifying foreign DNA, it would be useless without the proteins that chop up the foreign DNA. To have all the required machinery appear at the same time is only possible when they are designed together. Chance processes can’t manage such fancy developments at the same time (but some people hope otherwise anyway).See Jennifer Doudna: “It was almost as if CRISPR had co-evolved with cas [CRISPR associated system] genes, it didn’t seem possible to have one without the other.” [p. 63] [The cas proteins are the ones that cut up the foreign DNA.]This system therefore displays irreducible complexity wherein several precise components are present to allow for a system to be functional. When only part is present, the part that is there will not work and it will be lost from the cell.
  3. Apparently the CRISPR system in various microbes also operate using the same principles (a common blue print) but the actual molecules that operate the system are quite different. When we see variations on a common theme (blue print) then we again see the action of a mind. The blue print is an idea, not a material object.

Related Resources

  • CRISPR Basics (YouTube, 48 min) Jennifer Doudna introduces CRISPR basics in 6 minutes and then goes on to discuss uses of this tool, anti-CRISP systems and finally ethical issues connected to the use of CRISPR.
  • A Crack in Creation: The New Power to Control Evolution (Book). Jennifer Doudna and Samuel Sternberg. 2017.  Bodley Head. pp. 281. A chatty book on the discovery of CRISPR and the development of techniques to exploit this system. Doudna covers a lot of ethical issues involved with this tool for genome editing. She takes evolution for granted but is not convincing in her remarks on this issue. This book is somewhat technical but meant for the general reader.

Related Terms

  • DNA Code
  • RNA (Ribonucleic Acid)
  • Blueprint
  • Convergence
  • Convergence (Specific Example)
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