Friday, February 15, 2008

The Implications of Genetic Entropy

In previous posts I’ve explained that humans have a mutation rate many times higher than once thought. Some documentation for this point from the standard scientific literature:

Crow, J.F. 1997. The high spontaneous mutation rate: a health risk? PNAS 94:8380-8386.

Kondrashov, A.S. 1995. Contamination of the genome by very slightly deleterious mutations: why have we not died 100 times over? J. Theor. Biol. 175:583-594.

Loewe, L. 2006. Quantifying the genomic decay paradox due to Muller’s ratchet in human mitochondrial DNA. Genetical Research 87:133-159.

The best discussion of these implications to date is found in John Sanford’s book Genetic Entropy and the Mystery of the Genome (Elim Publications, 2005). Another prescient book that recognizes the devolutionary pattern of decay over time is Not by Chance, by Dr. Lee Spetner (Judaica Press, 1997).

The latter book approached the subject by examining known cases of beneficial mutations, discovering that even beneficial mutations tended to be beneficial only because of fluke side effects; the mutations themselves generally causing a breakdown in the overall efficiency and health of the cell. For example, some antibiotics can be blocked by mutations that alter the porin channels that antibiotics use to enter a cell. But such mutations also reduce or destroy the effectiveness of the porin channels as transport paths for useful cellular materials (after all, the porin channels didn’t exist solely so antibiotics could enter and kill the cell!)

Using a model with 100 mutations/child, Dr. Sanford used Mendel’s Accountant ( to generate a genetic fitness curve. Starting with a fitness of 1, the result is a logarithmically declining curve that drops below 0.5 by the 150th generation and 0.2 by 500 generations. In other words, genomic decay is catastrophic within historical timescales.

This explains why humans suffer extensively from genetic maladies and diseases on a widespread, and apparently increasing, scale. Such suffering is difficult to explain in a traditional Darwinian framework. If evolution by natural selection is so powerful as to be able to craft hypertechnological systems such as the human eye, blood clotting mechanisms, photosynthesis, etc., then it is hard to understand why genetic flaws that can be so easily rectified by comparison, persist widely in the population.

John Woodmorappe, in his book Noah’s Ark: A Feasibility Study, documented the fact that the vast majority of diseases are believed to be of recent origin within the past few thousand years, even in traditional evolutionary timescales. (This was a refutation to the claim that Noah’s family would have to bear a host of parasites and disease-causing organisms through the Cataclysm.) The recent appearance of diseases corresponds well with the evidence for rapid genomic decay.

Given the pace of decay over even a few hundred generations, there are a few reasonably safe conclusions that can be drawn:

  1. The human genome originated within the fairly recent past (thousands to tens of thousands of years ago).
  2. The genetic health of the human genome as originally constituted was much higher than at present.

It has been truly said that science cannot prove the Bible. On the other hand, it can be shown to be consistent with it, and inconsistent with competing worldviews. In this case, the idea of ‘upwards’ evolution from simple to complex is plainly falsified; modern mutation evidence is consistent instead with the Book of Genesis in its description of a perfect beginning followed by a Fall and decay (the Curse). It is also consistent with a timescale reflecting a recent origin for the human race, and inconsistent with a traditional evolutionary timescale of several million years for the history of man.

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