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Genetic mutation

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A genetic mutation is a change to the nucleotide sequence (the "letters") of a DNA molecule of an organism[1]. Mutations can be caused by environmental agents such as ultraviolet light, nuclear radiation, or certain chemicals; or by mistakes that occur during DNA synthesis while the cell is dividing (undergoing mitosis).[2] Mutations are the only mechanism offered to provide the new genetic information required to produce the evolutionary "family tree".

Contents

Types of mutations

There are several types of mutations:

  • Substitution: a mutation that substitutes one base for another (i.e. switching an A to a G)
  • Insertion: extra base pairs are inserted into into a new place in the DNA
  • Deletion: a section of DNA is lost, or deleted
  • Frameshift: one base is deleted, causing the codons to become useless. For example, using the sentence "The fat cat sat," if the initial "t" were to be deleted, the sentence would become "Hef atc ats at."[3]
  • Duplication: in a duplication mutation, a portion of genetic material or a chromosome is duplicated or replicated, resulting in multiple copies of the involved region

Copying mistakes

Mutations are essentially "copying mistakes". If a typist is typing up a copy of a book, they might occasionally make a mistake, so that the copy is not exactly the same as the original. However, such mistakes are virtually never going to add something new to the book. Rather, they are more likely going to corrupt (damage) the information contained in the book.

And this is what scientists observe genetic mutations doing also. Biophysicist Lee Spetner wrote:

All point mutations that have been studied on the molecular level turn out to reduce the genetic information and not to increase it. ... Not even one mutation has been observed that adds a little information to the genome.[4]

Evolutionists will often claim that new information can be introduced by means of gene duplication, but duplication is merely an additional copy of existing information, not new information. If a recipe book contains 100 recipes, and you copy one page and add it to the book, you don't now have 101 recipes. You simply have 100 recipes, with one of them included twice. Thus no new information is introduced by duplication.[5]

They will also claim that new information can be introduced by duplication followed by mutations in the duplicate, so that the duplicate is no longer an exact duplicate, but something different. However, this process also fails to introduce new information. The first problem is that, as with any other mutation, the mutation, if not neutral, damages or destroys the information; it doesn't introduce new information.[6]

The second problem is that most such duplications are actually harmful to the organism, if not fatal. And finally, most duplications undergo degenerative mutation so that they end up non-functional.[6]

Evolutionist Lynn Margulis wrote:

Although random mutations influenced the course of evolution, their influence was mainly by loss, alteration, and refinement. One mutation confers resistance to malaria but also makes happy blood cells into the deficient oxygen carriers of sickle cell anemics. Another converts a gorgeous newborn into a cystic fibrosis patient or a victim of early onset diabetes. One mutation causes a flighty red-eyed fruit fly to fail to take wing. Never, however, did that one mutation make a wing, a fruit, a woody stem, or a claw appear. Mutations, in summary, tend to induce sickness, death, or deficiencies. No evidence in the vast literature of heredity changes shows unambigious evidence that random mutation itself, even with geographical isolation of populations, leads to speciation.[7]

Consequences for evolution

Evolution proposes that life began with a very basic life form, and from that developed all the various life forms that we have today. As that original living thing would not have had the genetic information for hair, blood, eyes, feathers, bones, or a whole host of other things, the massive amounts of genetic information for all these things would need to be generated somehow throughout evolutionary history. The evolutionary view is that those genetic changes resulted from mutations.

But even if, one day, scientists conclusively demonstrate a mutation adding new genetic information,[8] it provides extremely weak evidence for evolution, because the odd, extremely rare exception to the rule is never going to supply the massive quantities of new information required by evolution as it would be swamped by all the information-destroying mutations.[9]

Effects of mutation

Mutations are responsible for causing many diseases. So far, over 10,000 mutations have been identified as causing diseases in humans.[10]

The rate of mutations in humans has long been of concern to geneticists. In the 1950s it was thought that humans accumulated deleterious mutations at the rate of 0.12 to 0.3 per person per generation, and there was concern with the possibility of the rate approaching one deleterious mutation per person per generation. That is, if the rate was one per person per generation, then natural selection would have to eliminate 100% of new lives in order to stop the human genome deteriorating. In fact, natural selection can only afford to eliminate one person out of three for each generation, given that the fertility rate is now three children per two adults.[11]

However, modern research has shown that the mutation rate is at least 100 nucleotide substitutions per person per generation, with one expert saying that it could be as high as 300 per person per generation. Even if 97% of these 100 mutations occur in parts of the genome where they cause no harm, there's still three deleterious mutations per person per generation.[12]

Natural selection is therefore incapable of eliminating most of these deleterious mutations, except by eliminating the species. So rather than being a mechanism that drives evolution, as evolutionists claim, mutations are destroying life.[9]

Heritability of mutations

Evolution proposes that natural selection will favour mutations that improve the "fitness" of the species. However, many other factors influence the likelihood of mutations being passed on to future generations.

Natural selection does not favour mutated genes at all. Natural selection favours organisms. If an organism has one "good" mutation and ten "bad" mutations, the result (in principle) is that the "good" mutation will not be selected, because selection works at the level of the organism, not the mutations. So the organism does not survive, and the good mutation is lost.

Furthermore, natural selection only works when all else is equal. A mutation might cause a particular organism to be "fitter" in that it can produce more offspring, but that particular organism fails to survive to breeding age because it is eaten by some other creature, it is unlucky enough to be killed off in a drought, or any number of other reasons which mean that natural selection fails to have an opportunity to favour that good mutation.

Another possibility is that, in sexually-reproducing species, that particular good mutation simply fails to get passed on.

Geneticist John Sanford refers to all this as "noise":[13]

Consider seeds falling off a tree. Some seeds will land on fertile ground ideal for growth. But most seeds will land on places that are too dry, too wet, too many weeds, too much shade, too many people, etc. The result will be great diversity in the health and vigor of the resulting trees, and huge differences in their survival and reproduction. But almost all of this "natural selection for the fittest", will really only be selection for the luckiest, not the genetically superior.

Bibliography

  • Sanford, J. C., "Genetic Entropy & the Mystery of the Genome", FMS Publications, Third Edition, 2008, ISBN 978-0-9816316-0-8

References

  1. University of Utah Genetic Science Learning Center
  2. University of Utah Genetic Science Learning Center: What Causes DNA Mutations?
  3. University of Berkeley's Understanding Evolution: Types of DNA Mutations
  4. Spetner, Lee, Not by Chance! Judaica Press, New York, p. 138, 159–160, 1998, quoted in One Blood, chapter 2
  5. Batten, Don, Dawkins and the origin of genetic information, 29 September 2007.
  6. 6.0 6.1 Liu, Yingguang, and Moran, Dan, Do new functions arise by gene duplication?, Journal of Creation 20(2):82–89, August 2006.
  7. Lynn Margulis and Dorion Sagan, Acquiring Genomes: A Theory of the Origins of the Species, Basic Books, 2002, p. 29, ISBN 9780465043910, quoted by Casey Luskin, On the "Settled" Science of Darwinian Theory, Tennessee's Evolution Lobby Is Simply Bluffing, Evolution News and Views, April 5, 2012.
  8. There have been a very few claims of new genetic information, but most if not all are inconclusive or disputed.
  9. 9.0 9.1 The extinction of the human genome appears to be just as certain and deterministic as the existence of stars, the death of organisms, and the heat death of the universe. Sanford, 2008, p.83 (emphasis in original)
  10. Online Mendelian Inheritance in Man
  11. Sanford, 2008, p. 33.
  12. Sanford, 2008, p. 34.
  13. Sanford, 2008, p.91
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