Blood types and their origin
(Countering the Critics)
by Jonathan Sarfati
Introduction
One of the commonest questions asked of creationists is: ‘How did the great
variety of humans arise from a single human pair?’ It is ironic that many
people who regard this as unanswerable believe something far more incredible, that
all living organisms have arisen from a single cell, which itself arose from non-living
chemicals. If one can believe that random mutation and natural selection is an adequate
explanation for those huge changes (with vast increases in information content),
then these mechanisms surely suffice for the creationist view of minor changes (which
do not involve generation of new, functional information).
The Creation/Fall theory can account for all the variation in humanity by pointing
out that the original pair had an enormous genetic variability. Reshuffling of this
variability, some loss of complexity due to mutations, and natural selection can
explain all the current variability. This has been explained in detail in
The Creation Answers Book Chapter 181. The book points
out that a wide range of skin colours can arise from just four genes for melanin
distribution.
The different eye colours arise from light scattering off melanin particles in the
iris, with the observed colour depending on the amount and depth of the melanin.
The blueness of the sky is similarly caused by light scattering off air molecules,
while the pink/red sunset results from the shallower angle of the sun’s rays.
Dust particles enhance this effect, often leading to very vivid sunsets. Albinism
is caused by a harmful mutation greatly reducing or destroying the ability to synthesise
melanin. Without melanin in albinos’ eyes, the blood vessels are visible,
so the eyes are pink.
However, particles-to-people evolution must postulate a mechanism which can produce
new complex information. Natural selection cannot produce information;
it can only select from the information available to it.
Origin of the Blood Types
One aspect of the wide variety of humans is all the different blood types. The following
explanation covers the main A, B and O
blood types 2.
The A and B blood groups are caused by different
antigens (substances which provoke immune responses) on the surface of the red blood
cells. Their production is under the control of the DNA. The antigens develop from
a red blood cell surface precursor called H substance, which is common to A,
B and O. Type A results from
the placement of N-acetylgalactosamine by the enzyme type A transferase
on the H substance. Type B results from attachment of galactose
to H by Type B transferase.
Type O is the result of a simple point mutation that greatly reduced
or destroyed the ability of Type A transferase to attach N-acetylgalactosamine
to H substance. Note that this is an example of loss of information,
so is irrelevant to particles-to-people evolution. This ineffective Type A
transferase is called circulating protein. The ineffectiveness of type O’s
circulating protein depends on the point in the DNA where the mutation occurred,
because some type Os attach more N-acetylgalactosamine to H than others. This sometimes
causes discrepancies among blood banks. The mutations probably happened early in
human history, since O is the most common blood group. Unattached
H substance itself is an antigen which results in the rare blood type Bombay or
Oh.
There is one gene in humans that controls the ABO blood type. There
are three versions of the gene, or alleles: A, B,
or O. Since the gene is always present as a pair of alleles, with
one inherited from each parent, the possible
genetic make-up of any individual is AA, BB,
AB, AO, BO, or OO.
The O allele is recessive to the A or B,
meaning that in the presence of the A or B allele,
the blood type is determined by the A or B allele.
That is, an AO person has A-type blood; a
BO person has B-type blood, whereas only an OO
person has O-type blood. Anyone with O-type blood
is called a universal donor because their blood lacks the A or
B antigens so that O-type blood can be given to
a person with A, B or AB type
blood. If, for example, A-type blood is given to a person with
B-type blood, an allergic reaction can result in death of the recipient.
For a husband and wife to pass on all alleles to their children, they need to, between
them, have the A, B, and O alleles.
So Adam and Eve could have had any of the following genetic make-ups:
AO and BO, AB and OO,
AB and AO, AB and BO,
AA and BO or BB and AO,
that is, any combination where both parents have all three alleles between them.
Another possibility is that the O gene arose later by mutation
as discussed above. If so, the parents would only need to have A
and B between them, so they could both be AB,
or AA and AB, BB and AB
or AA and BB.
If Adam and Eve were genetically AO and BO, for
example, their children could have had AB, AO,
BO or OO genetic make-up, giving AB,
A, B, or O blood types. Indeed,
about 25% of their children would have been of each type (see the Punnet Square
— below) 3.
If Adam and Eve had 56 children, as per Jewish tradition, then there would have
been about 14 of each blood group.
Possible Function of Blood Types
One anti-creationist asked: ‘What use are blood types, which only make blood
transfusions difficult?’ and called the variety a ‘flawed design’.
However, the claim of ‘flawed design’ is unscientific unless one can
demonstrate a better design. And the first rhetorical question presumes that just
because we are ignorant of a use, there can be no use. In fact, it is in principle
impossible to prove that an organ is useless, because there is always the possibility
that a use may be found in future.
This has happened with over a hundred alleged useless vestigial organs which are
now known to be essential 4. The thymus
was one gland which was thought to be useless, but now we know that it is the first
organ to produce lymphocytes in the embryo, and where the T lymphocytes are made.
‘The thymus is central to the development and function of the immune system5.’ Severe immunodeficiencies
result when the thymus is rendered useless or destroyed. This is the main problem
with AIDS victims. Their T lymphocytes are destroyed by the virus.
Even the appendix, widely thought to be a useless evolutionary vestige, contains
lymphatic tissue and has a role in controlling bacteria entering the intestines.
It functions in a similar way to the tonsils at the other end of the alimentary
canal, and are known to increase resistance to throat infections, although once
also thought to be useless organs6.
It is also a mistake to assume that there is no use for the blood types. There are
immunological relationships between A, B and H
antigens and those of bacteria and vegetable matter and how our bodies respond to
invading micro-organisms without destroying self. There also seems to be a relationship
between blood type and heart problems (not the claimed Type A behaviour
relationships). Type A blood has more cryoprecipitate which blood
banks want. The mutant Type O blood type seems to predispose people
to develop stomach ulcers7. The variety
in blood groups could also mean that some blood diseases could not destroy the whole
population, if the pathogen was adapted to a particular blood type.
References
- Batten, D.J. (ed.),
Catchpoole, D., Sarfati, J.D. and
Wieland, C. 2006.
The Creation Answers Book, Creation Book Publishers, Brisbane,
Australia. Return to text.
- This explanation is based on an article in Creation in the
Crossfire (Torrance, CA: South Bay Creation Science Association). The information
for the article came mostly from the Technical Manual of the American Association
of Blood Banks. Return to text.
- Batten, DJ, 1996.
It’s in your blood. Creation 18(1):45.
Return to text.
- Wiedersheim claimed that there were over 180 vestigial organs in
the human body, in Wiedersheim, R., The Structure of Man: an Index to his Past History.
Translated by H. and M. Bernard (London: Macmillan, 1895).
See a refutation of the ‘vestigial organs’
argument for evolution.
A thorough creationist treatment is Bergman, J. and Howe, G., “Vestigial Organs”
Are Fully Functional (Kansas City: Creation Research Society Books, 1990).
Return to text.
- Basic and Clinical Immunology, 4th Ed., p. 65. Return to text.
- Glover, W.J. 1988. The Human Vermiform
Appendix — a General Surgeon's Reflections. Journal of Creation
3(1):31–38. Return to text.
- See ref 2. Return to text.
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