No. 131: SEP-OCT 2000
Usually left unsaid is the fact that the present blueprint covers only 2-3% of the territory. That's right, 97-98% of the human genome isn't mapped at all. This uncharted territory is assumed to be "junk" or "nonsense" DNA that plays no role in heredity. Want to bet that this assumption is correct? And don't forget that genes jump around. The genome is really a moving target.
Genes also work in concert. It is not one gene coding for one protein, which then has a singular role in creating an operational human being. For example, some 5,692 genes are active in breast-cancer cells. Genes may also have multiple roles. Our present blueprint of the human genome does not display all the mobility and complex interrelationships of the genes.
We do know that genes are the blue-prints for the manufacture of proteins. Of these, there may be over 1,000,000 different -- more than ten times the number of genes! These multitudinous proteins are continually being created and transported to where they perform their assigned tasks and are eventually deconstructed. It is this population of proteins (collectively the "proteome") that develops organisms and gives them life. We do not begin to have a blue-print for the proteome, which really tells us how life works.
Then, there are epigenetic influences. "Epigenetic?" Yes, the manufacture of proteins according to genome blueprints is altered by chemical groups that attach themselves to strands of DNA. Methyl groups, for example, can completely silence genes. Scientists are strugglingto understand just how epigenetic factors affect inheritance and the creation of new species.
There is much more to biology than DNA and genes. The genome is complex enough, but the proteome adds still another layer of complexity, and epigenetic spoons stir the pot further.
(Ezzell, Carol; "Beyond the Human Genome," Scientific American, 283:64. July 2000. Anonymous; "Some Baseless Speculations," The Economist, p. 83, May 27, 2000. Cr. J. Cieciel. Note the pun in the second title!)
Comment. Let us look down the scale of complexity to the relatively small number of chemical elements, and even further down to electrons and protons, perhaps as far as quarks, gluons, etc. Is it reasonable to suppose that within these supposed elementary particles there exists the potential for the unfolding of the million-member proteome? Are electrons and protons fraught with such immense potential? Can or must the apparently simple properties of the elementary particles lead to the flowering of human beings? Or even to more complex entities?
(White, Robb; "Armadillos, and Dangerous," Natural History, 109:86, July-August 2000.)
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