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Monday, 11 January 2016

Another failed Darwinian prediction III

The DNA code is not unique:
Shortly after the discovery of the DNA code, which is used in cells to construct proteins, evolutionists began theorizing how it evolved. The same code was found in very different species which means that the same code was present in their distant, common ancestor. So the DNA code arose early in evolutionary history and remained essentially unchanged thereafter. And since it arose so early in evolutionary history, in the first primitive cell, the code must not be unique or special. For how could such a code have evolved so early in the history of life? As Nobel Laureate Francis Crick wrote in 1968, “There is no reason to believe, however, that the present code is the best possible, and it could have easily reached its present form by a sequence of happy accidents.” (Crick) Or as one widely used undergraduate molecular biology text later put it, “The code seems to have been selected arbitrarily (subject to some constraints, perhaps).” (Alberts et. al., 9) And an evolution textbook further explained, “The code is then what Crick called a ‘frozen accident.’ The original choice of a code was an accident; but once it had evolved, it would be strongly maintained.” (Ridley, 48)

In other words, somehow the DNA code evolved into place but it has little or no special or particular properties. But we now know that the code’s arrangement uniquely reduces the effects of mutations and reading errors. As one research study concluded, the DNA code is “one in a million” in terms of efficiency in minimizing these effects. (Freeland) Several other studies have confirmed these findings and have discovered more unique and special properties of the code. One found that the DNA code is a very rare code, even when compared to other codes which already have the error correcting capability. (Itzkovitz) Another found that the code does not optimize merely one function, but rather optimizes “a combination of several different functions simultaneously.” (Bollenbach) As one paper concluded, the code’s properties were “unexpected and still cry out for explanation.” (Vetsigian)

References

Alberts, Bruce., D. Bray, J. Lewis, M. Raff, K. Roberts, J. Watson. 1994. Molecular Biology of the Cell. 3d ed. New York: Garland Publishing.

Bollenbach, T., K. Vetsigian, R. Kishony. 2007. “Evolution and multilevel optimization of the genetic code.” Genome Research 17:401-404.

Crick, Francis. 1968. “The origin of the genetic code.” J. Molecular Biology 38:367-379.

Freeland, S., L. Hurst. 1998. “The genetic code is one in a million.” J. Molecular Evolution 47:238-248.

Itzkovitz, S., U. Alon. 2007. “The genetic code is nearly optimal for allowing additional information within protein-coding sequences.” Genome Research 17:405-412.

Ridley, Mark. 1993. Evolution. Boston: Blackwell Scientific.

Vetsigian, K., C. Woese, N. Goldenfeld. 2006. “Collective evolution and the genetic code.” Proceedings of the National Academy of Sciences 103:10696-10701.

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