Over the many years since I graduated from medical school, the knowledge of how the complex and unique DNA molecule functions in the cell has increased greatly. Much of what is now basic knowledge of molecular genetics was only touched on when I was in high school and medical school. The human genome had not yet been fully decoded. The more I learn about this amazing molecule, the more convinced I am of the impossibility that it evolved by random chance under the guiding hand of natural selection.
DNA is a molecule that contains a vast amount of information that instructs the cell what proteins to make. These proteins include not only structural elements such as skin, bones, and nails but also all the biologic catalysts (enzymes) for our myriad and indispensable metabolic reactions. Without these catalysts, our reactions would not proceed at the rate that is required for our survival. We would not exist.
Consider, for instance, the genetic code. Let’s begin with the complex double helical DNA molecule already in existence. It has two backbones made of sugar-phosphate molecules linked together in long chains, with its “rungs” joining the backbones being made of a combination of four nucleotides: adenine, guanine, cytosine, and thymine. Note that a random arrangement of these four nucleotides will yield no information for the cell.
In order for DNA to contain the “blueprint”, the masterplan, these nucleotides are arranged in a coded form. As a matter of fact, every three nucleotides correspond to one of twenty different amino acids. Once assembled in the proper order, a chain of amino acids will fold into a three-dimensional shape which is a protein. We have in total sixty-four codes. If this came about by a random process, how can such a code evolve? How would natural selection favour part of a code and not another? A few amino acids do not make a protein and would confer no selective advantage on an organism; more fundamentally, of what would the organism be made before the coding for proteins existed?
Furthermore, if one sees a paragraph of words written in code, an intelligent being is needed to find the cipher. Randomly typing letters on a page will never result in an intelligent coded message.
And that is not all. We have a very tiny structure inside our cells, called the ribosome, and its job is to “read” or decode the message in the DNA. As a matter of fact, part of the DNA is made into a single strand containing the codes, called the RNA. The RNA is held by the ribosome, and the ribosome will move along three nucleotides at a time and assemble the correct amino acid chain. This is done with the help of a special type of RNA called the transfer RNA which is linked to one of the twenty amino acids. The transfer RNA has a region that is exactly complementary to the three-nucleotide code being “read”. If the particular transfer RNA fits the code, the amino acid will be accepted by the ribosome.
You see, for this cell to make the right protein which may confer survival advantage, not only do we need to develop coded information in the DNA molecule, we also have to have a structure called the ribosome in our cells that is capable of decoding the DNA, and we also have to develop somehow transfer RNAs that are linked to amino acids, which will fit onto the nucleotide code! There is absolutely no advantage to having only one part of this long, but ingenious process; all the parts are essential in order to produce a correct protein, the building block of the organism. How can all these parts containing all these subparts, containing coded information all evolve at the same time? While part of the parts is evolving, there will be no survival advantage to the organism (in fact, it would probably be harmful to the organism), and according to the theory of evolution that organism will die off.
On top of that, a cell has varying methods of controlling which part of the DNA molecule will be copied into the RNA that goes to the protein-making process. Thus, despite having a unique set of DNA codes, each organism has ways of turning off and on certain parts of the DNA molecule, fine-tuning the process so that the cell will only make what is needed.
Biology is replete with such examples. The process of photosynthesis, for instance, involves numerous enzymes (which are proteins), each encoded in the DNA of the cell. In the extremely improbable event that one of the enzymes did evolve, the plant still cannot carry on photosynthesis, still cannot make food for itself out of carbon dioxide and water, and there is absolutely no selective advantage! No, you have to have all the enzymes evolve at once.
And that is not all. If the plant evolved to make food such as glucose in this case, you also have to have a mechanism to break down the food to release energy for the plant to grow and survive. That would require a whole new set of different enzymes just to cover the complicated processes of glycolysis, Krebs cycle, and the electron transport chain.
The biological world screams intelligent design. What else can explain it? Indeed, the Psalmist said it well in 19:1:
The heavens declare the glory of God; And the firmament shows His handiwork.
The evolutionist rejects God and tries again and again to find alternate and godless explanations to the intelligent designs we see in nature, much like a petulant child repeatedly saying, “But I don’t want to believe God made these!”