Mutations mildly deleterious

The human situation is not understood, but it is possible that, for every severe mutation detected by laboratory test systems, 20 or more mildly deleterious mutations also occur. 

There are conditions under which mildly deleterious mutations could contribute to protein evolution. If a second mutation occurs in a protein-coding gene that has experienced a deleterious mutation, it might compensate for the harmful effect of the first. If the doubly mutated gene were functionally equivalent to the wild-type gene, it would be fixed by genetic drift. 

For operational reasons, the under-wrapping or packing deficiency of a protein may be defined as v = % dehydrons in the set of backbone hydrogen bonds. As we focus on any functionally competent fold, the anecdotal examples we harvested suggest a clear trend u(archea) < v(bacteria) < (unicellular eukaryotes) < < (higher eukaryotes). This trend probably follows from the fact that mildly deleterious mutations have a better chance to prevail and get fixed in species with smaller... 

Mildly deleterious mutations are eventually eliminated from the gene pool, albeit much more slowly compared with lethal mutations. Because mildly deleterious mutations are common, there is probably important variation in the number of such mutations that we carry. That is, humans vary in genetic quality. Thus, we have an incentive to distinguish between potential mates. Because females make a larger investment than males in reproduction, they have an... 

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