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Mutation

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Types of mutation.JPG

A mutation is any spontaneous heritable change in DNA sequence that contributes to genetic variability. It results from 2 possible mechanisms.

  1. Cellular accidents during processes like replication, recombination, or transposition.
  2. Exposures to foreign mutagens, such as chemicals or ultra violet rays.

If even one of the nucleotides in a gene is changed to another, then a new variation of the allele has been added to the population, and a different amino acid may be assembled into the protein during gene expression.

Contents

Types

Mutations are classified as harmful, beneficial, or neutral.

  • Harmful - spontaneous changes to genes will render proteins dysfunctional, and can lead to physical deformation, cancer, or death.
  • Beneficial - mutations that produce some benefit can theoretically happen even through the destruction of the protein.
  • Neutral - mutation where there is no effect (also known as a silent mutation). A neutral mutation either results in a codon that is translated into the same amino acid during gene expression, or the substituted amino acid has no effect on protein function. The following table shows several codons that are each translated into the same amino acid. In each case, the 3rd nucleotide in the codon would be a neutral mutation if changed.
Amino Acid Serine Leucine Proline Arginine Threonine
Codon TCT CTT CCT CGT ACT
Codon TCC CTC CCC CGT ACC
Codon TCA CTA CCA CGT ACA
Codon TCG CTG CCG CGT ACG

New information

It is clear that new gene alleles are accumulating in populations today, but there are two possible sources for these changes; mutations, and intentional changes introduced by genetic recombination. The theory of evolution attributes the continued production of genetic diversity to mutations, but evolutionists overlook the fact that the cell was intelligently designed. The cellular machinery was programmed to perform a level of self genetic engineering, and is editing genes systematically so that organisms can adapt to a wide variety of environmental conditions.[1]

Evolutionists contend that mutation, acted upon by natural selection is the mechanism for evolutionary advancement. While this mechanism has the power to change the genome over time, most biological evolution is actually due to genetic recombination followed by natural selection. There are many examples put forward by evolutionary biologists that attempt to show how new genes have been introduced into the genome of an organism. However, in most documented cases it merely illustrates the built-in plasticity or variation within the original created kind. Merely shuffling of already existing genes becomes woefully inadequate if the observational science is followed.

Despite the few examples of beneficial genetic mutations it is unrealistic to assume that this information produced through changing already existing DNA would then be acted on again many more times by other related mutations to build radically different and complex structures than what was there previously. This is to say that mutations are not a reasonable means of producing cascading morphological change from one kind of animal to another but merely speciation.

Obviously mutations can indeed cause dramatic phenotype change from environmental pressures. Many experiments have been performed on fruit flies (Drosophila) where poisons and radiation induced mutations. However, the problem is that they are always deleterious. The Drosophila experiments showed an extra pair of wings on a fly, but these were a hindrance to flying because there are no accompanying muscles. Therefore, these flies would be eliminated by natural selection. Even in the case of mutations which can change the amount of DNA possessed by an organism, an increase in the amount of DNA does not result in increased function. Biophysicist Dr. Lee Spetner in his book, Not by Chance: Shattering the Modern Theory of Evolution, analyzed examples of mutational changes that evolutionists claimed were increases in information, and demonstrated that they were actually examples of loss of specificity, meaning loss of information.

In all the reading I've done in the life-sciences literature, I've never found a mutation that added information. … All point mutations that have been studied on the molecular level turn out to reduce the genetic information and not increase it." - Spetner

and

We see then that the mutation reduces the specificity of the ribosome protein and that means a loss of genetic information. ... Rather than saying the bacterium gained resistance to the antibiotic, it is more correct to say that is lost sensitivity to it. ... All point mutations that have been studied on the molecular level turn out to reduce the genetic information and not increase it.
[2]

Georgia Purdom from AiG, Ph.D. of molecular genetics, has stated,

Mutations only alter current genetic information; they have never, ever been observed to add genetic information; they can only change what is there. I have a lot of papers come across my desk of supposedly mutations that have added genetic information, and I've read them all, and I've looked at them all, and never, once have I seen one that has added genetic information; they just don't do that.
[3][4]

Mathematical challenge

Mutations either beneficial, negative or neutral are rare instances. They happen on average about once in every 10 million duplications of the DNA molecule (107, a one followed by 7 zeroes). For evolution to progress, organisms require a series of related mutations to occur. The odds of getting two mutations that are related to one another is the product of their separate probabilities. If every 107 duplications of DNA a mutation occurs the equation would start to look like this; 107 x 107 or 1014. a one followed by 14 zeroes, a hundred trillion. Mutations which are related or not would barely change finch beak sizes due to drought, or change the shape of a fly wing.

What are the odds of getting three related mutations? That is, again taking into account the mutation rate of duplicated DNA, one in a billion trillion or 1021. Suddenly the ocean isn't big enough to hold enough bacteria to make that chance very likely. You can quickly tell that at just three related mutations, evolution via related, dependent mutational change through natural selection as its mechanism to produce truly novel information or molecule-to-man change is woefully inadequate. [2] [3]

Mutation load

Although beneficial mutations are theoretically possible, natural selection does not act at the molecular level, but rather it operates only at the level of the organism. It selects only those mutations that produce a physiological change, which alters the survival or reproductive rate of the organism. As such, for every rare beneficial mutation that might occur, countless numbers of harmful mutations are accumulating within the genome of the organism - producing what is known as a "mutation load".

April of 2007 paper by the Proceedings of the National Academy of Sciences (PNAS) states that:

Our theoretical findings indicate that mutator hitchhiking can set in motion a self-reinforcing loss of replication fidelity, but the question of how a process as robust as natural selection could allow this to happen remains. The key fact is that natural selection, although eminently robust, is a short-sighted process that favors traits with immediate fitness benefits. The fitness cost of mutator hitchhiking is generally not anticipated because of the slow accumulation of deleterious load. When a mutator hitchhikes with a new beneficial mutation, a simple model shows that the increased deleterious load due to the mutator is in fact suppressed during the spread of the beneficial mutation. Indeed, the full fitness cost of the mutator is only realized well after the beneficial mutation has stopped spreading (SI Text). A mutator may therefore enjoy the immediate benefit of producing a new beneficial mutation without anticipating the eventual increase in deleterious load. Because of this delay in the accumulation of deleterious load, natural selection can drive mutation rate up to the point of no return, where fMmMu2 becomes the dominant term (Fig. 4A); even if the increase in deleterious load is lethal, it is not anticipated (Fig. 4B). At the population level, this failure to anticipate the establishment of a lethal deleterious load is partly due to the sharpness of the threshold separating lethal from viable mutation rates (22, 24), such that there is no slow fitness decrease to "warn" of impending extinction. [4]

References

  1. Genetic Variability by Design by Chris Ashcraft. Journal of Creation 18(2) 2004.
  2. Mathematical Challenges to the Neo-Darwinian Interpretation of Evolution By Paul S. Moorhead, Martin M. Kaplan; Wistar Institute Symposium; Science Vol. 160. no. 3826, p. 408, 1967
  3. Dr. Gary Parker. Creation: Facts of Life [1]
  4. Complete genetic linkage can subvert natural selection by Philip J. Gerrish, Alexandre Colato, Alan S. Perelson, and Paul D. Sniegowski, Proceedings of the National Academy of Sciences USA, published online before print April 3, 2007

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