Mutations
Eden
In the beginning, the first human pair had no deleterious mutations (or none, at least, not shared by all humans today). The project of writing human DNA, by whatever engineering team wrote it, was finished, and the genome contained the code as intended to optimally function.
This human pair multiplied rapidly into the human race. Inbreeding was not an issue in the first several generations, due to the lack of harmful mutations that make inbreeding an issue.
The Fall
By the time humanity reached a large population size, harmful mutations had become a normal fixture of the population. Severe mutations are immediately eliminated by natural selection, but milder (though still harmful) mutations ride from one generation to the next, and are eliminated more gradually.
The elimination of non-lethal mutations by natural selection is substantially assisted by “truncation selection,” made possible by the mixing of genes in sexual reproduction. Gene-mixing allows individuals who are born with a large number of mutations, to be very unlikely to reproduce, due to the combined effect of those mutations. And thus natural selection is able to eliminate many harmful mutations without sacrificing so many individuals in the process.
The sexual mixing of genes also allows the chance creation of many very high-functioning individuals who are at or near the competence and capacity of the original human pair. Thus, the population, though riddled with harmful mutations, still can have a significant minority of nearly unharmed individuals. This segment of the population, as a general rule, enjoys the good life that humans were ultimately designed to live.
The majority of the population consists of non-high-functioning individuals, who suffer various kinds of misery as a result of their mutations, and for the most part are doomed to be used as a semi-functional, manageable resource by the high-functioning indviduals, to support the good life enjoyed by those high-functioning individuals.
Salvation
The human population invented religion partly out of a desire to prematurely satisfy the thirst for knowledge, but more importantly to neutralize the threat of anger in the non-high-functioning majority — anger which constantly threatens to attack the high-functioning, successful people out of resentment of their good life. All major religions, by exploiting the human thirst for ultimate knowledge, teach people that they will face some sort of highly undesirable, divine “justice” if they lash out in resentment at the high-functioning individuals.
This is also why many high-functioning individuals throughout history have been enthusiastic proponents of religion. Whenever they are intellectually tempted to weigh the possibility that religion is mostly made-up fantasy (especially in its moralistic judgment stories), then deep down they realize that the teachings of heaven and hell, or of karma, or of judgment-based reincarnation, are protecting them from sharing in the misery of the non-high-functioning people. This is almost nakedly admitted in religious texts, such as this Bible quotation:
The fool hath said in his heart, “There is no God.” They are corrupt, they have committed abominable acts; there is no one that doeth good.
Enlightenment
With the advent of modern technology, we face the first striking changes to this situation.
First, the modernization of communications causes a nasty side-effect: communism.
Once modern communications have outlived the generations that saw them mature, this side-effect subsides, but resentment remains. The religious solution being no longer effective due to mature global communications (see my comments in Mechanism pp. 99-100), such resentment finds expression in forms milder than communism, such as voters, common jurors, street protestors, and life-appointed judges who each act on their respective opportunities to stick it to the high-functioning people without fear of repercussion.
We also see many individuals lashing out at the system any way they can, when faced with a window to do so with impunity — a phenomenon nicely summarized by John Gabriel’s Greater Internet Fuckwad Theory.
And, of course, we find ourselves in a period of semi-regular killing sprees, performed by individuals who have reached the end of their “maybe I’m a high functioning person who’s just been unlucky thus far” rope.
Resurrection
While none of these new affronts seriously threatens to take down modern civilization, nor prevent the steady advance of technology, they do put painful thorns in the toes of the high-functioning (and many of the non-high-functioning as well), and thus give those high-functioning individuals an irritating, ongoing incentive to give up on the now-untenable religious solution, and take seriously the genetic solution, which is:
first to develop a technology of genetic threat detection, that zeros in on those individuals who carry a genetic predisposition to commit gross anti-social acts,
then develops further into a technology of identifying and proactively repairing all genetic damage, which will cure the whole problem of mutations once and for all.

