Chance Probability of DNA

http://www.answersingenesis.org/home/Area/isd/marcus.asp

First published in
In Six Days
Science and origins testimony #18

Edited by John F. Ashton

Dr. Marcus is research officer at the Cooperative Research Centre for Tropical Plant Pathology, University of Queensland, Australia. He holds a B.A. in chemistry from Dordt College, an M.S. in biological chemistry and a Ph.D. in biological chemistry from the University of Michigan. Dr. Marcus’s current research deals with novel antifungal proteins, their corresponding genes, and their application in genetic engineering of crop plants for disease resistance.

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Amazing as the DNA molecule may be, there is much, much more to life than DNA alone; life is possible only if the DNA blueprint can be read and put into action by the complex machinery of living cells. But the complex machinery of the living cell requires DNA if it is going to exist in the first place, since DNA is the source of the code of instructions to put together the machinery. Without the cellular machinery, we would have no DNA since it is responsible for synthesizing DNA; without DNA we would have no cellular machinery. Since DNA and the machinery of the cell are codependent, the complete system must be present from the beginning or it will be meaningless bits and pieces.

In order to emphasize this codependence of the cellular machinery and DNA, let us examine some proteins (i.e., the machinery) that are directly involved in the conversion of the DNA blueprint into more proteins. Before we list the processes and proteins associated with converting DNA information into proteins, we should emphasize the following points: (1) each and every step in the overall process absolutely requires protein(s) that are unique and extremely complex; and (2) these unique and complex proteins can only be produced by the overall process in which they themselves are critically involved.

The making of RNA4 from a DNA template is a critical first step in the process of protein formation. For RNA to be synthesized, no fewer than five different protein chains5 must cooperate. Four of these proteins form the RNA polymerase complex and the last one tells the RNA polymerase where to start reading the DNA template. This enzyme complex must recognize where to start transcribing DNA into RNA; it must then move along the DNA strand, adding individual building blocks6 to the growing RNA chain; and lastly, it must know where to finish the transcription process.

It is not enough, however, simply to make one kind of RNA; three different types of RNA are required in the process of making proteins: messenger RNA (mRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA). Molecules of mRNA carry the information extracted from the DNA blueprint which encodes the protein to be synthesized; rRNA molecules make up a critical component of ribosomes (discussed below); and tRNA is responsible for carrying individual amino acids to the site where they will be added to a new protein. Before tRNA molecules can serve their proper function, however, they must be charged with a suitable amino acid in order that it can be added on to a growing protein chain at the appropriate time. At least 20 different aminoacyl-tRNA synthetase proteins are necessary to attach individual amino acids to the corresponding tRNA molecules (at least one for each type of amino acid).

Once mRNA, tRNA and rRNA molecules have been synthesized, it is then necessary to translate the information from the mRNA into a protein molecule. This process is carried out by a huge complex of proteins called the ribosome. These amazing protein synthesis “machines” contain multiple different proteins, together with various ribosomal RNA molecules all associated into two main subunits. In a simple bacterium such as E. coli, ribosomes are composed of some 50 different proteins7 and three different rRNAs!

The reactions mentioned above are only the core reactions in the process of synthesizing proteins; we have not even discussed the energy molecules that must be present for many of these reactions to proceed. Where is the energy going to come from to produce these energized molecules? How will the cell harvest energy unless it has some sort of mechanism for doing so? And, where is an energy-harvesting mechanism going to come from if not from pre-encoded information located in the cell?

A quick summation will reveal that the process of converting DNA information into proteins requires at least 75 different protein molecules. But each and every one of these 75 proteins must be synthesized in the first place by the process in which they themselves are involved. How could the process begin without the presence of all the necessary proteins? Could all 75 proteins have arisen by chance in just the right place at just the right time? Could it be that a strand of DNA with all the necessary information for making this exact same set of proteins just happened to be in the same place as all these proteins? And could it be that all the precursor molecules also happened to be around in their energized form so as to allow the proteins to utilize them properly?

Needless to say, without proteins life would not exist; it is as simple as that. The same is true of DNA and RNA. It should be clear that DNA, RNA and proteins must all be present if any of them are going to be present in a living organism. Life must have been created completely functional, or it would be a meaningless mess. To suggest otherwise is plain ignorance (or perhaps desperation). So, we truly have a “which came first?” problem on our hands. I believe the answer is, of course, that none of them came first! God came first; He designed and then created all of life with His spoken Word. DNA, RNA and protein came all at exactly the same time. It is extremely difficult to understand how anyone could believe that this astoundingly complicated DNA-blueprint translation system happened to come about by chance.

Meaningful molecules could not have arisen by chance
Now let us consider the probability of just one of the above 75 proteins coming about by chance. Consider a smaller than average protein of just 100 amino acid residues. If all the necessary left-handed amino acids were actually available, and if the interfering compounds, including right-handed amino acids, were somehow eliminated, and if our pool of amino acids were somehow able to join individual amino acids together into protein chains faster than the proteins normally fall apart, then the chances of this random 100 amino-acid protein having the correct sequence would be 1 in 20100 possible sequence combinations; 20 available amino acids raised to the power of the number of residues in the protein, i.e., 1 in 1.268 x 10130, or 1 in 12, 680, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000!!!

To put this number in some perspective, we must do some calculations. The reader may wish to skip ahead if the absurdity of chance giving birth to order is already appreciated. Let us take a more-than-generous scenario and see how desolate the theory of evolution becomes in view of the probabilities. The earth has a mass of around 5.97 x 1027 grams. If the entire mass of the earth were converted to amino acids, there would be in the order of 3.27 x 1049 amino acid molecules available.8 If all of these molecules were converted into 100-residue proteins,9 there would be 3.27 x 1047 proteins. Since there are 1.27 x 10130 possible combinations of amino acids in a 100-mer protein (see above), a division of the number of possibilities by the number of proteins present on our hypothetical globe shows that the chances of having just one correct sequence in that entire globe of 100-mer proteins is 1 in 3.88 x 1082!!!10

Even if each of these 3.27 x 1047 100-mer proteins could be rearranged many times over into different sequences during the timespan of the earth, the chances that one correct sequence would be produced are still not close to being realistic. Consider that there are “only” 1.45 x 1017 seconds in the mythical evolutionary age of the earth.11 It can be calculated that each and every 100-mer protein in that hypothetical earth would need to rearrange itself an average of 2.67 x 1065 times per second in order to try all possible combinations!12 The 100-amino-acid molecules could not even come close to assembling and disassembling that quickly. It is physically impossible.

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This is about half of the article. The full article can be read here:

http://www.answersingenesis.org/home/Area/isd/marcus.asp