L.A. Moran lamoran at
Wed Sep 26 00:01:56 EST 1990

The following topic will be debated in a course run by Antony Courtney of the
Lawrence Berkeley Laboratory;

     "Should congress provide extra incentives to those parents whose genetic
      profiles indicate their children will be healthy?"

Antony claims that one of the arguments in favor of this proposition is;

     "...that Congress has a responsibility to ensure the health
      and well-being of the population, and should encourage people to act
      responsibly in deciding about children.  I think most would agree that 
      it would be NICE if people decided not to have children if they knew 
      those children would have some genetic disease, hence removing such 
      "inferior" genes from the gene pool.  Furthermore, (a) other nations
      will be doing it, and it may have a far more elitist bent to it, 
      and (b) congress isn't "stopping" anyone from having children, they
      are just providing "encouragement" for those that will have healthy 

I hope Antony doesn't object to a "foreigner" putting in his 2 cents worth
concerning a proposed American law.

I can recognize two intents of the proposed legislation. One the one hand it
discourages the birth of individuals with a genetic disease. This may have
some benefit to American society which outweighs the problems with legislating
eugenics (although I doubt it). A second intent, implied in the quotation
above, is to "improve" the gene pool of that segment of the population of
Homo sapiens that is subject to the legal authority of the Congress of the
Unnited States of America. The legislation would reward male and female
individuals who propose mating, provided that there is no evidence that such
a mating could potentially produce offspring with a genetic defect. Other
matings would not be rewarded with "extra incentives".

The argument that "inferior" genes can be removed from the population by
swamping them with "superior" genes seems spurious. Many of the so-called
"inferior" genes are recessive alleles and the homozygous individuals are
already at a reproductive disadvantage (ie. dead). This doesn't seem to have
had much effect on the gene pool of the human population as long as the 
population approximates random interbreeding.

If the phenotype of the homozygote was not detrimental to reproductive
ability (ie. baldness) it would be very difficult to affect the gene
pool even if all homozygotes were sterilized. Many biology books discuss
this obvious limitation of eugenics. For most recessive alleles it would
take about 25,000 years to lower the frequency of the allele to half of its
current level.

The proposal is not even as efficient as this mechanism (assuming that it
was workable). Americans would have to wait a very long time before seeing
any effect, and during that time Congress would have to insure that the
gene pool didn't become "contaminated" by immigration! Can you imagine how
big a wall the USA would have to build along the Canadian border? (-:

It seems unlikely that any legislative body could be convinced to enact a 
politically contoversial law that wouldn't have the desirable effect for 
more than 25,000 years. Of course, many legislatures have enacted dumb laws 
because they don't understand the science (I could give you several Canadian 
examples but probably everyone on the net could contribute examples from their 
own countries).

If you really want the population of the United States to be purged of
"inferior" genes then a better way to do it (speaking scientifically) would 
be to sterilize everyone who is heterozygous for ANY "inferior" gene. 
Unfortunately there may not be enough fertile breeders left to maintain
a sizable population.

-Larry Moran
Dept. of Biochemistry

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