No. 89 Creation, Mutation, and Variation

By Gary E. Parker, Ed.D.*

"Enormous," "tremendous," "staggering"-all these are adjectives

used by geneticist Francisco Ayala to describe the amount of

variation that can be expressed among the members of a single

species.' Human beings, for example, range from very tall to very

short, very dark to very light, soprano to bass, etc., etc. This

tremendous amount of variation within species has been considered

a challenge to creationists. Many ask: "How could the created

progenitors of each kind possess enough variability among their

genes to fill the earth with all the staggering diversity we see

today and to refill it after a global flood only a few thousands

years ago?"

If we use Ayala's figures, there would be no problem at all.

He cites 6.7 % as the average proportion of human genes that show

heterogneous allelic variation, e.g., straight vs. curly hair, Ss.

On the basis of "only"6.7 % heterozygosity, Ayala calculates that

the average human couple could have 1021111 children before they

would have to have one child identical to another! That number, a

one followed by 2017 zeroes, is greater than the number of sand

grains by the sea, the number of stars in the sky, or the atoms in

the known universe (a "mere" 1080)!

A single human couple could have been created with four

alleles (two for each person) at each gene position (locus). Just

two alleles for vocal cord characteristics, V and v, are

responsible for the variation among tenor (VV), baritone (Vv), and

bass (vv) singing voices in men, and hormone influences on

development result in soprano (VV), mezzo-soprano (Vv), and alto

voices (vv) as expressions of the same genes in women.

Furthermore, several genes are known to exist in multiple copies,

and some traits, like color, weight, and intelligence, depend on

the cumulative effect of genes at two or more loci. Genes of each

different copy and at each different locus could exist in four

allelic forms, so the potential for diversity is staggering

indeed!

Even more exciting is the recent discovery that some genes

exist as protein coding segments of DNA separated by non-coding

sequences called "introns." In addition to other functions, these

introns may serve as "cross-over" points for "mixing and

matching" sub units in the protein product.2 If each subunit of

such a gene existed in four alielic forms, consider the staggering

amount of variation that one gene with three such sub units

could produce! it is quite possible that such a clever-and

created-mechanism is the means by which the information to

produce millions of specific disease-fighting antibodies can

be stored in only a few thousand genes.

Besides the positive contributors to genetic diversity

described above, there is also one major negative contributor:

mutation. Believe it or not, orthodox evolutionists have tried to

explain all the staggering variation both within and among

species on the basis of these random changes in heredity called

"mutations." What we know about mutations, however, makes them

entirely unsuitable as any "raw materials for evolutionary

progress."

As Ayala says, mutations in fruit flies have produced

"extremely short wings, deformed bristles, blindness and other

serious defects." Such mutations impose an increasingly heavy

genetic burden or genetic load on a species. In her genetics

textbook, Anna Pai makes it clear that "the word load is used

intentionally to imply some sort of burden" that drags down the

genetic quality of a species.' The list of human mutational

disorders, or genetic diseases, for example, has already passed

1500, and it is continuing to grow.

By elimination of the unfit, natural selection reduces the

harmful effects of mutations on a population, but it cannot solve

the evolutionist's genetic burden problem entirely. Most

mutations are recessive. That is, like the hemophilia ("bleeder's

disease") gene in England's Queen Victoria, the mutant can be

carried, undetected by selection, in a person (or plant or animal)

with a dominant gene that masks the mutant's effect.

Time, the usual "hero of the plot" for evolutionists, only

makes genetic burden worse. As time goes on, existing mutants

build up to a complex equilibrium point, and new mutations are

continually occurring. That is why marriage among close

relatives (e.g. Cain and his sister) posed no problem early in

human history, even ti-though now, thanks to the increase in

mutational ]Odd with time, such marriages are considered most

unwise. Already, 1% of all children born will require some

professional help with genetic problems, and that percentage

doubles in first-cousin marriages.

Genetic burden, then, becomes a staggering problerti for

evolutionists trying to explain the enormous adaptive variation

within species on the basis of mutations. For any conceivable

favorable mutation, a species must pay the pi-ice or bear the

burden of more than 1000 harmful mutations of that gene. Against

such a background of "genetic decay," any hypothetical favorable

mutant in one gene would invariably be coupled to harmful changes

in other genes. As mutational load increases with time, the

survival of the species will be threatened as indtiiigs produce a

greater percentage of offspring carrying serious genetic

defects.

As the source of adaptive variability, then, mutations (and

orthodox evolution theories) fail completely. As a source of

"negative variability," however, mutations serve only too well,

Basing their thinking on what we observe of mutations and their

net effect (genetic burden), creationists use mutations to help

explain the existence of disease, genetic defects, and other

examples of "negative variation" within species.

Mutations are "pathologic" (disease-causing) and only

"i-nodify what preexists," as French zoologist Pierre-Paul Grassi

says, so mutations have "no final evolutionary effect."4 Instead,

mutations point back to creation and to a corruption of the

created order. There are 40-plus variants of hemoglobin, for

example. All are variants of hemoglobin; that points back to

creation. All are less effective oxygen carriers than normal

hemoglobin; that points back to a corruption of the created order

by time and chance.

At average mutation rates (one per million gene duplications),

a human population of one billion would likely produce

a thousand variant forms of hemoglobin, Lethal mutants

would escape detection, and so would those that produced only

minor changes, easily masked by a dominant normal gene. It is

likely then, that the 40 or so recognized hemoglobin abnormalities

represent only a small fraction of the genetic burden we bear at

the hemoglobin position.

According to a new school of thought, "the neutral theory of

molecular evolution," much of the staggering variation within

species is due to mutations that are either neutral (without

effect) or slightly deleterious." Such a theory offers no comfort

to the evolutionist trying to build grander life forms from

mutations, but it is an expected consequence of the

creation-corruption model. Interestingly, says Kimura, the

amount of variation within species is too great for selection

models of evolution, but too little for the neutral theory. He

suggests that recent "genetic bottlenecks" have set back the

"molecular clock" that otherwise ticks off mutations at a

relatively constant rate. Scientists who recognize the fossil

evidence of a recent global flood are not at all surprised, of

course, that data suggest recent "genetic bottleneck" which

only a few of each kind survived!

Now, what about the time factor iii ttie creatordliori model? How

How long would it take, for example, to produce all the different

shades of human skin color we have today?

There are several factors that contribute subtle tones to

skin colors, but all people have the same basic skin coloring

agent, ttie protein called melanin. We all have melanin

skin color, just different amounts of it. (Not a very big

difference, is it?) According to Davenport's study in the West

Indies, the amount of skin color we have is influenced by at least

two pairs of genes, A-d and B.b.

How large would it tdke AaBb parents to have children with

all the variations in skin color we see today? Answer: one

gencration. Just one generation. As shown in the genetic square,

one in 16 of the children of AdBb parents would likely have the

darkest possible skin color (AABB); one brother or sister in 16

would likely have the lightest skin color (aabb); less than half

(6/16) would be medium-skinned like their parents (any two

"capital letter" genes); and one-quarter (4/16) would be a

shade darker (3 capital letter genes) dnd a shade lighter (1

capital letter).

 

MAXIMUM VARIATION (unable to show graph variation)

 

What happened as the descendants of our first parents (and of

Noah's family) multiplied over the earth? If those with very dark

skin color (AABB) moved into the same area and/or chose to marry

only those with very dark skin color, then all their children

would be limited to very dark skin color. Similarly, children of

parents with very light skin color (aabb) could have only very

light skin, since their parents would have only "small a's and

b's" to pass on. Parents with genotypes AAbb or aaBB would be

limited to producing only childi-eii with medium-skin color. But

where people of different backgrounds get back together gain,

as they do in the West Indies, then their children can once

again express the full range of variation.

Except for mutational loss of skin color- (albinism),

then, the human gene pool would be the same now as it might have

been at creation-just four genes, A, a, B, b, no more, no less

Actually, there are probably more gene loci and more

alleles involved, which would make it even easier to store

genetic variability in our created ancestors. As people

multiplied over the earth (especially after Babel), the

variation "hidden" in the genes of two average-looking parents

came to visible expression in different tribes and

tongues and nations.

The same would be true of the other created kinds as well:

generalized ("average looking") progenitors created with large

and adaptable gene pools would break up into a variety of more

specialized and adapted subtypes, as decendants of each

created kind multiplied and filled the earth, both after

creation and after the Flood.

There is new evidence that members of some species

(including the famous peppered moth) may actually "choose"

environments suitable for their trait combinations.6 If

"habitat choice" behavior were created (and did not have to origi-

nate by time, chance, and random mutations!), it would reduce the

genetic burden thdt results when only one trait expression is

"fittest," and it would also greatly accelerate the process of

diversification within species.

Research and new discoveries have made it increasingly easy

for creationists to account for phenominal species

diversification within short periods of time. These same

discoveries hove only magnified problems in orthodox neo-Darwinian

thinking. It is encouraging, but not surprising, therefore, that

an increasing number of students and professionals in science are

accepting the creation model as the more logical inference from

scientific observations and principles.

The scientist who is Christian can also look forward to the

end of genetic burden, when the creation, now "subjected to

futility" will be "set free from it' bondage to decay, and

obtain the glorious liberty of the children of God" (Romans 8).

 

References

 

1. Ayala, "Mechanisms of Evolution, "Scientific American, V 239

2. Kolata, Gina, "Genesis in Pieces" , Science V. 207

3. Pai, Anna Foundations of Genetics, NY McGraw Hill pp. 248-280

4. Grasse, Pierre-Paul, Evolutions of Living Organisms, NY Academic Press

5. Kimura, Motoo, "The Neutral Theory of Molecular Evolution, "Scientific

American V. 24

6. Powell, Jeffrey, and Charles Taylor, "Genetic Variation in Diverse

Environments, "American Scientist, V67