| Creation Truth Outreach, Inc. Pamphlet |
| © 2007 Creation Truth Outreach, Inc. All Rights Reserved. This pamphlet may be freely copied provided it is copied in its entirety, its contents are not altered in any manner, and additional or tighter copyright restrictions than these are not imposed on it. Revised May 5, 2008 |
| Chapter 4. Limitations On Natural Selection. 5. Natural Selection Works Best With Linear Genes, Not Stacked Ones. Discussions on natural selection tend to assume a one-to-one relationship between genes and enzyme sequences. One gene controls one trait as an expression of the effects of one enzyme. Thus, a mutation to a particular gene may hopefully, occasionally give a survival advantage to some trait. However, multi-cellular organisms do not have a one-to-one relationship between genes and enzymes. Instead, the sequence of codons in a gene defining a particular amino acid sequence gets interrupted by what are called interons. These represent control points in the DNA information sequence which do not get decoded into amino acids. The interons represent boundaries between short segments of information that do get decoded. Here is the catch. A single gene in the DNA may actually be used to build half a dozen or so different enzymes. The different enzymes make use of different segments of information contained within the same gene. A specific enzyme gets assembled from the various segments by specialized control enzymes. 23 For instance, it is now thought that human beings have only about 30,000 genes in their genome. However, these 30,000 genes code for perhaps 100,000 different enzymes. That is an overall average of 3 different enzymes per gene. 24 Normally, no enzyme uses all the segments. The choice of segments determines the structure and usage. The problem is that a mutation that might supposedly be beneficial for the structure of one enzyme could be harmful to the others formed from the same gene. It is hard enough to get a beneficial mutation to begin with. Experiments with fruit flies during the 1950s did not give observable evidence of a single known beneficial mutation. Yet, multiple thousands of harmful ones were observed. As a result of this situation, it is not enough for a mutation to somehow be of benefit in the changes it makes to a particular enzyme. The ripple-effect changes to the other enzymes built from the same code segments must not harm them lest any advantage to the first quickly becomes lost. If one thinks his way through how enzymes are actually formed, with various coils and sheets pieced together in an exactly prescribed manner, he can realize the difficulties in changing the shape of one enzyme without changing the shape of another enzyme when both use the same segment of a common gene. Of course, as a creationist, I believe that this extraordinary complexity of the code was placed there by a Creator. He let us find out about it so that we may be in awe of His extreme intelligence and wisdom. |