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ABOLISH THE ABSURDITIES
It's OK to Believe in Both Creation and Evolution

by
D. R. Cruise

This book is now in print. [more info]

Appendix B: A Collection of Simulations

Appendix B examines some of the technical aspects of eugenics. Definitions for technical terms appear in the Glossary.

A person's genetic information is stored in chromosome pairs, one member of each pair comes from each parent. Let us restrict ourselves to the case where the normal trait is dominant. If an individual gets normal code from each parent, the geneticist calls the individual, homozygous dominant. For simplicity, let us identify this individual as NN.

If the individual gets normal code from one parent, and an undesirable code from the other, the geneticist calls the individual, heterozygous. We will refer to that individual as NU. Note that, while the individual does not exhibit the trait, he can pass the trait to successive generations.

If an individual gets the undesirable code from both parents, the geneticist calls that individual, homozygous recessive. We will refer to the individual as UU. In the examples above, this individual is the victim of a genetic disease.

Consider Sickle Cell Anemia. Society may have the wish, based on eugenic motives, to sterilize all NU and UU individuals. Then only NN individuals remain. They cannot pass the trait to future generations. Therefore, Sickle Cell Anemia is immediately eliminated.

However, in historical times, Sickle Cell genetic code had an advantage. The NU individuals have extraordinary resistance to malaria.

In those times, when malaria epidemics struck, many NN individuals were lost; but the resistance of the NU individuals blunted the impact of the epidemic.

Let us turn now to another approach that some people may wish to use against an undesirable genetic trait. Again we will call the three genotypes, NN, NU, and UU. The N stands for the normal trait as before and U stands for an unspecified but undesirable trait. The eugenic tool we discuss here is abortion.

Let us assume that prenatal DNA testing can tell us whether the unborn child is UU, NU or NN. We employ other assumptions as follows: (1) Trait, N, completely dominates U, and (2) a UU individual does not survive until child bearing age, or is unable to bear children, for some reason related to the disease. (In other words. the UU individual is a genealogical dead-end.) The author admits these are worst-case assumptions.

The abortion technique would target only the UU children. Under the assumptions of the previous paragraph, these children can appear only when both parents are NU. In this case there will be three live births for every abortion.

Among the surviving children are both NN and NU types. None of them show the undesirable trait. However, the NU individuals can carry the trait to the next generation. The strategy attempts to be more patient than the sterilization approach and to allow the undesirable trait to disappear gradually.

However, it is a fact that the undesirable trait will not decrease at all. The underlying presence of the trait will increase! A computer simulation using the program in Appendix A shows this.

Not everyone has the computer hardware and software required to run the program. Therefore, the results of nine test cases are presented here for the reader's consideration. The computer produced these results by using the sample input shown in Appendix A.

Case (0): Equal NN and UU; equal survival rates of NN, NU, & UU

 Read in frequencies of the NN, NU & UU genotypes: 
  0.5000   0.0000   0.5000
 Read in survival rates of NN, NU and UU genotypes: 
  0.7000   0.7000   0.7000

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
           1       2500       5000       2500          0
           2       2500       5000       2500          0



This is the classical case of the intermingling of dominant and recessive traits first described by Mendel. If the populations of NN and UU persons are equal, then the results obtained for the next generation are: one fourth homozygous dominant (NN), one fourth homozygous recessive (UU) and one half heterozygous (NU). Equilibrium is reached after one generation. (In this case, the meanings of the terms, normal (N) and undesirable (U), do not apply.)

Note that the recessive trait maintains its presence. A recessive trait does not disappear merely because it is recessive. A recessive trait would only tend to disappear, if the individuals that possess it, have a low survival rate.

Case (1): NN/NU=9/1; UU survival=0; eugenics=0; NU not favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7000   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:  
 Chosen eugenics is: 0

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
         1       9025        950         25          0
        80       9801        198          1          0



Cases (1) through (8) show what happens under various circumstances when the UU individuals have zero survival rates. The starting (generation zero) ratio of NN to NU populations is arbitrarily set to a ratio of nine-to-one for the eight cases. This is done for comparison.

The reader is welcome to try other initial values but they will not change the equilibrium results. The equilibrium result is shown on the bottom line (the 80th generation in the case above).

The computer program defines equilibrium as the point where the production of a genotype such as UU, or in some cases, NU, approaches zero. When this is not possible, equilibrium is defined as the point where the changes from the previous generation approach zero. Often this never happens mathematically. Therefore, an arbitrary criterion is chosen. The program sets this to one in 10,000. The reader is welcome to try other criteria.

Cases (1) though (4) show the results for the situation where NN and NU have equal survival rates. In real life this may not be true. Therefore, cases (5) through (8) will consider the other possibility.

Case (1) (above) shows the situation where no eugenics is attempted. Note that it takes 80 generations for the recessive trait to reach the criterion of disappearance. (This would be 1600 years if there were 20 years per generation.)

This demonstrates that recessive traits are very persistent, even when disadvantaged. (The same is not true of a dominant trait that has zero survivability. When NN, and therefore NU, have zero survival rates, the dominant trait disappears in one generation.)

Case (2): NN/NU=9/1; UU survival=0; eugenics=1; NU not favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7000   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:  
 Chosen eugenics is: 1

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
         1       9040        941         19          0
        56       9776        223          1          0



Case 2 demonstrates a situation not mentioned in chapter 8. It considers the case where people react to an event instead of trying to anticipate the event. It assumes that having a UU child will so traumatize the couple that they decide not to have any more children. So they employ birth control to make sure it does not happen. This is probably realistic to some extent.

Normally the program assumes that all couples have three children (or whatever number the user inputs). To handle Case 2 the program specifies that {NU}{NU} marriages will, on the average, produce fewer children.

Specifically, the number of kids per {NU}{NU} marriage is reduced from three to 2.3125. The result of this intervention is that the number of generations required for {UU} to decline to a frequency of one in 10,000, has been lowered from 80 to 56. There is, therefore, a eugenic advantage over case (1).

Case (3): NN/NU=9/1; UU survival=0; eugenics=2; NU not favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7000   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:  
 Chosen eugenics is: 2

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
         1       9033        967          0         33
       142       9828        172          0          1



Case (3) shows the results for eugenic abortion. In this case, amniocentesis identifies the UU children, which are then aborted. The counter intuitive result of the simulation is that it now takes 142 generations to reach the point where only one UU abortion per 10,000 live births is necessary. Without eugenics it took only 80 generations to reduce the frequency of UU births to one in 10,000 (case (1)).

The results can be explained. Two-thirds of the aborted UU individuals are replaced with highly surviving NU individuals. The NU individuals are the principal reason for the persistence of the recessive trait; and abortion increases their frequency. Therefore, abortion is not good eugenics (even if we were to agree that there is such a thing as good eugenics).

Case (4): NN/NU=9/1; UU survival=0; eugenics=3; NU not favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7000   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:  
 Chosen eugenics is: 3

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
           1       9000       1000          0          0
           2       9000       1000          0          0



Case (4) analyzes the genetic counseling approach to eugenics. It disallows {NU}{NU} marriages entirely and permits {NN}{NN} marriages only after all NU individuals have married NN individuals. The computer results show that equilibrium occurs immediately. (The word, marriage, is used here in a clinical sense rather than in a legal or religious sense; perhaps mating is the better term.)

The good news is that UU individuals never appear. The bad news is one cannot marry whomever one wants and the prevalence of NU individuals does not decrease. In other words the counseling approach has to continue indefinitely to maintain its benefits.

Case (5): NN/NU=9/1; UU survival=0; eugenics=0; NU favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7200   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:  
 Chosen eugenics is: 0

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
         1       9001        973         26          0
       281       9467        526          7          0



Cases (5) through (8) show results for the situation where, as before, the recessive trait is non surviving, but where a mechanism exists that favors the recessive trait. To accomplish this, we give the NU individuals a slightly higher survival rate (.72) than the NN individuals (.70).

This mechanism is inspired by the historical resistance of NU individuals to malaria when the recessive trait (U) is sickle cell anemia. Other mechanisms may be considered but they would probably lead to similar results.

Case (5) is the base line case for favored NU survivability where no eugenics is attempted. Here we see that equilibrium requires 281 generations. What is worse, we see that the occurrence of UU individuals never falls below seven cases per 10,000. Because of the mechanism favoring NU individuals, the undesired trait never disappears.

Case (6); NN/NU=9/1; UU survival=0; eugenics=1; NU favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7200   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:  
 Chosen eugenics is: 1

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
         1       9016        963         20          0
       289       9562        434          4          0



Case (6) shows the results for favored NU survival when {NU}{NU} couples are frightened into restricting further births by the arrival of a UU child. (This happens in the same fashion as in case (2).) Here we see that the equilibrium number of UU births is four per 10,000 compared with seven in the base line case (5). Approximately the same number of generations is required. As in case (2) we see a eugenic advantage to the trauma induced birth control scenario.

Case (7): NN/NU=9/1; UU survival=0; eugenics=2; NU favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7200   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:  
 Chosen eugenics is: 2

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
         1       9009        991          0         35
       253       9249        751          0         20



Case (7) shows the case of favored NU survival where abortion is the eugenics of choice. Here we see that it takes 253 generations to reduce the required number of abortions from 35 to 20. They will never be reduced further because equilibrium has occurred.

Observe that NU has been reduced to 751 per 10,000 compared to 526 per 10,000 in the base line case (5) (no eugenics). This means that abortion actually increases the presence of the recessive trait in human society although it is hidden from view by the abortion of the UU individuals. Just as in Case (3), abortion turns out to be poor eugenics

In this case there would be even worse news in the future for those parents who do not wish to consider abortion as an option. They will discover that more children are born to them with the undesirable trait than would occur if the general population were not practicing eugenic abortion!

Case (8): NN/NU=9/1; UU survival=0; eugenics=3; NU favored:

 Read in the frequencies of the NN, NU & UU genotypes: 
  0.9000   0.1000   0.0000
 Read in the survival rates of NN, NU and UU genotypes: 
  0.7000   0.7200   0.0000
 Eugenics? None=0, Birth Cntrl=1, Abort=2, Counsel=3:
 Chosen eugenics is: 3

Generation   NN/10000   NU/10000   UU/10000   Aborts/10000
         1       8974       1026          0          0
        78       5000       5000          0          0
Not enough NN to go around



In case (8) we observe the results of genetic counseling in the case of favored NU survival. As in case (4), NU individuals may only marry NN individuals. The startling result is that after 77 generations there will no longer be enough NN individuals left to marry all the NU individuals.

This method causes a rapid increase of NU individuals and now some of them must go mateless. This means that, in this case, genetic counseling is even worse eugenics than abortion.

We can summarize the computed results in the following table. Here we consider neither the desirability nor the morality of birth control, abortion and selective mating. The result column merely shows whether eugenics succeeds in its own short term and long term objectives.

Case Number

Eugenic Method

Results

Cases (1) and (5)

No eugenics

(Base lines)

Cases (2) and (6)

Birth Control

Beneficial *

Cases (3) and (7)

Abortion

Bad eugenics

Case (4)

Mating restrictions

Neutral

Case (8)

Mating restrictions

Terrible eugenics



* While we see beneficial results in cases (2) and (6), we can dispute whether they are truly eugenics, because the behavior is induced by fear; it is not the result of a deliberate eugenic program of intervention.



Let us return briefly to the amazing results in Case 8. Eventually there will no longer be enough NN individuals left for all of the NU individuals to mate with! This implies that the genetic information obtained from DNA analysis may actually be dangerous.

Is it possible that information (of any kind) can be inherently dangerous? The author has been extremely reluctant to say, yes, and has struggled over this question.

However, it now appears to him that information can be dangerous in at least two instances.



    (1) Information can be dangerous when it is in the wrong hands.

    (2) Information can be dangerous when it is incomplete.

Even in the best hands, a eugenicist can never know the importance of supposedly undesirable genes against a future threat. Our uncertainty about the future means that genetic information will always be incomplete. Therefore, genetic information can be dangerous.

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