RNA World?

Evolutionists frequently state that life originated in a kind of organic soup. The idea is that the first cell arose from some kind of energy impulse propelling chemicals into one another. These collisions caused chemical reactions which generated the first cells.  Recently an idea called “RNA World” has gained traction.  Essentially the energy impulses created billions of strands of RNA which floated in this primordial soup. From these RNA strands, evolutionists say that the first cell arose. This article will examine the validity of that proposal by discussing what RNA is, how it works and whether it could have been the ancestral molecule.

RNA is the scientific shorthand for ribonucleic acid which is a derivative of deoxyribonucleic acid(DNA). RNA is produced by cells as a copy of a section of preexisting DNA strand.  RNA is a way of decoding DNA into information usable by the cell.  Once RNA has been transcribed from DNA, it is sent out of the cell’s nucleus for translation. Translation allows the cell to take the information provided by RNA and turn it into physical entities such as proteins.

An RNA molecule consists of three parts. The first part is a phosphate base. This molecule has the chemical formula of PO_4.  Under normal circumstances, phosphate would only form three chemical bonds due to something called valence electrons.  Without diving into all the chemistry, valence electrons are the negatively charged parts of an atom found closest to outside of the atom. In order to have all its needs met, an atom should have eight valence electrons, and they are will happily share in order to get to a full valence shell. This allows atoms to bond. Phosphate has five valence electrons so it only needs to share three more. Bonding with four oxygens means that Phosphate has more valence electrons than it needs.  This gives it a negative charge. The phosphate ends up with a -2 charge or two extra electrons.   Oxygen has six valence electrons, meaning each Oxygen molecule should need two extra valence electrons to have a full complement.  Three Oxygens meet their quota for desired valence electrons, but the fourth does not, adding a -1, giving the full molecule a -3 charge.  This molecule also has a basic pH, somewhere above seven.

The second part of the RNA molecule is the ribose sugar.  Ribose and the phosphate base, bind together to create the backbone of the RNA strand. Ribose has the chemical formula of C₅H₁₀O₅  but it shares two oxygens with the phosphate bases on either side of it.  As an organic molecule, containing carbon, it forms in a sort of ring anchored on an oxygen molecule.  The combination of ribose and the phosphate base form the backbone of the RNA molecule.  However, the piece that actually conveys the information, the nucleotide base, only attaches to the ribose.  It attaches at the first carbon molecule.

The nucleotide is the part of the RNA molecule that codes for information are the nucleotides. RNA has four different varieties of nucleotides, three of which are found in DNA as well.  Adenine, Guanine, and Cytosine are familiar to anyone who has ever studied the DNA helix.  Uracil, however, is unique to the RNA strand. With a chemical formula of C₄H₄N₂O₂  Uracil is a demethylated form of the Thymine structure found in DNA.  A demethylated form is a structure which has had a methyl group( CH₃) removed.  Adenine on a DNA strand binds to either Thymine or Uracil.  Uracil and Thymine both only bond to Adenine. Guanine and Cytosine bond to one another. A trio of these nucleotides in a row is referred to as a codon. Each codon codes for an amino acid.  Some amino acids are coded for by more than one codon.  Thus a chain of three hundred nucleotides would code for one hundred amino acids.  Several codons are referred to as “stop” codons because when they are translated, they end the formation of an amino acid chain. Once these amino acid chains form, they are folded into proteins.

The above is a very basic overview of what RNA is along with some snippets about how it works. RNA forms in the nucleus of a eukaryotic cell, when part of a DNA strand unzips. This part of the DNA strand codes for a particular protein or perhaps a chain of proteins. The RNA copies this information in a format which can be read by the ribosomes in the cytoplasm of the cell and translated into amino acids. Once the copying is complete, the RNA strand is sent to one of these ribosomes for translation. Upon the completion of the translation, the RNA degrades back into its constituent nucleotides.

Now we come to the salient point of this article, the question of whether RNA could be the ancestral molecule. Based on what we have outlined above, the answer appears to be a clear resounding no. RNA only forms as a copy of pre-existing DNA strand.  They are not known to form in any other fashion.  RNA, therefore, exists only as a temporary copy of existing information, it does not contain any information which does not already exist in the DNA strand. Further, the information carried by an RNA strand is useless without a pre-existing ribosome to translate the information into amino acids. However, ribosomes require information to form. In fact, RNA strands in the cell regularly carry the information needed for new ribosomes to existing ribosomes for translation. This allows the cell to replace damaged or aging ribosomes. This places evolutionists in the proverbial “chicken and egg” dilemma. Which came first, the ribosome that translates the RNA, or the RNA which has the information for the ribosome? Both had to be simultaneously existent or RNA would be useless.  In addition, an individual RNA strand which somehow arranged its codons in such a way that it had all the information required for the first cell is highly improbable. Remember that in each codon, there are three nucleotides. Each codon codes for a single amino acid. There are anywhere from hundreds to thousands of amino acids in each protein.  There are millions of proteins alone found in each cell.  To form just one cell, an RNA strand would need to be hundreds of millions to billions of nucleotides long.  The odds of forming an RNA strand that long with all the necessary information on it and in the correct order are staggeringly high. An RNA world would not be able to produce a single living cell, let alone the diversity we see today. Claiming that it did so fly in the face of all observational science.

Edit 01/21/2018:

The paper proposing the RNA World hypothesis has been retracted due to other scientists being unable to reproduce the results and significant experimental error.  Below is a link to the ICR article about the retraction. In the words of one of the scientists on the project “In retrospect, we were totally blinded by our belief”. In other words, their belief in evolution totally clouded their science. That however is an article for another day.

RNA World Paper retracted