Mystery of Genome

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Can natural selection create?

135

The molecular machinery underlying the coding, transcription, and translation of a protein is phenomenal. Ignoring all the other accessory proteins involved, just the design of the DNA/RNA sequence is mind-boggling. Although a simple protein has a few hundred component parts, the underlying gene that produces it has thousands of component parts.

All of these parts are

interacting and mutually-defining. Each nucleotide has meaning only in the context of all the others. Each nucleotide is polyfunctional - interacting with many other nucleotides. The DNA sequence defines regional 3-D chromatin structure, local protein binding, uncoiling, transcription, and also defines one or more RNA sequences. The RNA sequence defines RNA stability, RNA variable splicing, RNA processing, RNA transport, transcription efficiency, and protein sequence. We do not yet really understand how any single gene from a higher life form really works - not in its entirety. Not in the context of everything else that is happening in the cell. A single gene with all its interactions is still way too complex for us. When we consider the full complexity of a gene, including its regulatory and architectural elements, a single gene has about 50,000 component parts. I presume that this is more component parts than are found in a modern automobile. There is no simple linear path that leads car components to spontaneously become a functional car - mind is obviously required (actually, many brilliant minds). In the same way, there is no linear path of selection that can build a single gene from its individual nucleotides – a mind is likewise required. Yet a single gene is just a microscopic speck of irreducible complexity, within the universe of irreducible complexity that comprises a single cell. Life is itself the very essence of irreducible complexity - which is why we cannot even begin


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