Handedness: Left and Right 1 -- Science Disproves Evolution

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Genetic material, DNA and RNA, is composed of nucleotides. In living things, nucleotides are always �right-handed.� (They are called right-handed, because a beam of polarized light passing through them rotates like a right-handed screw.) Nucleotides rarely form outside life, but when they do, half are left-handed, and half are right-handed. If the first nucleotides formed by natural processes, they would have �mixed-handedness� and therefore could not evolve life�s genetic material. In fact, �mixed� genetic material cannot even copy itself (a).

Each type of amino acid, when found in nonliving material or when synthesized in the laboratory, comes in two chemically equivalent forms. Half are right-handed, and half are left-handed�mirror images of each other. However, amino acids in life, including plants, animals, bacteria, molds, and even viruses, are essentially all left-handed (b) �except in some diseased or aging tissue (c).

(a). �Equally disappointing, we can induce copying of the original template only when we run our experiments with nucleotides having a right-handed configuration. All nucleotides synthesized biologically today are righthanded. Yet on the primitive earth, equal numbers of right- and left-handed nucleotides would have been present. When we put equal numbers of both kinds of nucleotides in our reaction mixtures, copying was inhibited.� Leslie E. Orgel, �The Origin of Life on the Earth,� Scientific American, Vol. 271, October 1994, p. 82.

�There is no explanation why cells use L [left-handed] amino acids to synthesize their proteins but D [right-handed] ribose or D-deoxyribose to synthesize their nucleotides or nucleic acids. In particular, the incorporation of even a single L-ribose or L-deoxyribose residue into a nucleic acid, if it should ever occur in the course of cellular syntheses, could seriously interfere with vital structure-function relationships. The well-known double helical DNA structure does not allow the presence of L-deoxyribose; the replication and transcription mechanisms generally require that any wrong sugar such as L-deoxyribose has to be eliminated, that is, the optical purity of the D-sugars units has to be 100%.� Dose, p. 352.

(b). An important exception occurs in a component in cell membranes of eubacteria. There the amino acids are right-handed. This has led many to conclude that they must have evolved separately from all other bacteria. Because evolving the first living cell is so improbable, having it happen twice, in effect, compounds the improbability. [See Adrian Barnett, �The Second Coming: Did Life Evolve on Earth More Than Once?� New Scientist, Vol. 157, No. 2121, 14 February 1998, p. 19.]

(c). Recent discoveries have found that some amino acids, most notably aspartic acid, flip (at certain locations in certain proteins) from the normal left-handed form to the right-handed form. Flipping increases with age and correlates with disease, such as Alzheimer�s disease, cataracts, and arteriosclerosis. As one ages, flipping even accumulates in facial skin, but not other skin. [See Noriko Fujii, �D-Amino Acid in Elderly Tissues,� Biological and Pharmaceutical Bulletin, Vol. 28, September 2005, pp. 1585�1589.]

If life evolved, why did this destructive tendency to flip not destroy cells long before complete organisms evolved?