Can Genomic Selection problems be solved?
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on reproductive potential. These are the mutations immediately to the left of the near-neutral box, in Figure 3d. While artificial breeders may have a harder time seeing these subtle changes, natural selection (which is really just another way of saying differential reproduction) can generally “see” them - since by definition they affect reproductive probability. Furthermore, the effects of such mutations are partly additive, so natural selection can select for numerous minor mutants simultaneously. In fact, the way natural selection works is very elegant and appears to be designed to stabilize life - which would otherwise very quickly deteriorate. It is really a very wonderfully designed system. However, selection for minor mutations has significant limitations. The orderly elimination of minor mutations is seriously disrupted by what I call noise. Natural selection must see the mutants in terms of the mutants being a significant factor in reproductive probabilities.
Even “Mother Nature” can have trouble seeing
minor mutations, when other factors are significantly disturbing reproductive probabilities.
This is because the differences in
reproductive fitness caused by minor mutations are very subtle, and the effects of other factors can be very large. It is a little like trying to see the ripples produced by a pebble when thrown into a storm-tossed sea. All other variables which affect reproduction, when combined, will significantly interfere with natural selection against any given minor mutant.
For example, a high rate of accidental
deaths in a population will override and obscure the subtle effects of minor mutations.
Likewise, selection for lethal and near-
lethal mutations (which must automatically take precedence) will override the more subtle effects of minor mutations. The