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Modern Genetics began in 1900, with the discovery of Gregor
Mendels paper reporting two basic laws of inheritance. He is best
known for his work in plant breeding and is often referred to as
the father of modern genetics. Gregor Mendel, born Johann Mendel,
was an Augustinian monk and scientist. He was born in Heinzendorf
in the Austrian Empire (now part of Czech Republic) in 1822. His
father being a farmer and his grandfather a gardener, he knew a lot
about plants. Mendel studied philosophy at the University of Olmutz
for three years, and assisted his advisor, Johann Karl Nestler,
with conducting research on hereditary traits in plants and
animals. In 1843, Mendel entered the monastery of St. Thomas in
Brno. Upon entering the mon-astery, he elected to assume the
Christian name Gregor and thus became Gregor Johann Mendel. He was
ordained on August 6, 1847, just fifteen days after he turned
twenty-five, the minimum age for a priest, and appointed to a
teaching position in a local school. Recognized for excellence in
teaching, Mendel was sponsored by the Abbot of the monastery to
attend the University of Vienna in 1851, where he studied science
and math so that he could teach those subjects to the other monks.
In Vienna, Mendel transformed from a Silesian peasant to an
educated natural scientist. After 2 years of study in Vienna,
Mendel returned to Brno, where he taught school and began his
experimental work with pea plants. Mendels work shows that it does
not take a well-funded position in a huge laboratory with lots of
research apparatus, its paraphernalia and a team of assistants to
make key discoveries in science. He worked alone on a small plot of
land in his monastery. Between 1856 and 1863, Mendel analyzed
16,384 plants and expressed the results in a mathematical format.
He wisely chose pea plants as his experimental subject because they
had clearly defined patterns of inheritance. He painstakingly
crossed and backcrossed pollen and egg from the common pea plant to
reach a better understanding of inheritance. Imagine working on
thousands of plants, studying their inheritance, tabu-lating all
the results, and analyzing the results to draw conclusions: Mendel
did it all by himself. After his studies on the pea plants, he
developed the Law of Segregation and the Law of Independent
GREGOR MENDEL: Gardener of GodDr. Paul Kattupalli
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Assortment, which would come to be known collectively as Mendels
Laws of Inheritance. He witnessed that traits are inherited
separately and that characteristics that seem to be lost in one
generation may crop up again a generation or two later. He observed
that traits passed from parent to offspring as individual, discrete
units in a mathematically consistent manner. He proposed a
particulate theory of inheritance, which says that different
versions of heritable factors were responsible for inherited
traits, such as flower color. At Mendels time, plant and animal
breeders produced offspring by choosing the desirable varieties
from the parents. The prevailing view at that time was that the
factors responsible for inheritance blended together, yielding an
intermediate form. Mendel realized that Blending Hypothesis was
wrong. He concluded that the factors that determine inher-itance
are particulate and precise in their expression and, that each
individual must have two alleles for every gene, one from each
parent. He also demonstrated that an allele could be either
dominant or recessive, that is, if an individual possesses two
alleles for the same trait, only the dominant one will have an
effect. The allele that has no effect is called recessive. He
stated, hybrids form egg and pollen cells of different kinds, and
that herein lies the reason of the variability of the offspring.
Mendels brilliance was that the chromosomes that separate the
characters as sperm and egg form in meiosis (the special type of
cell division necessary for sex-ual reproduction) had not yet been
discovered. The significance of meiosis for reproduction and
inheritance
Mendels chose to conduct his experiments on pea plants because
they had clearly defined patterns of inheritance.
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was described only in 1890 by German biologist August Weismann.
After completing his research with plants, Mendel became interested
in patterns of heredity in honeybees. However, he had difficulty
determining definitive laws of inheritance due to trouble
controlling the mating patterns of the queen bee. He also had a
great interest in meteorology and astronomy and founded the
Austri-an Meteorological Society in 1865.
Mendel presented his research work in talks in February and
March of 1865 in a two-part lecture to a local scientific society,
Brno Natural Science Society. Later, in 1866, the lectures were
published as a forty-four-page article in the proceedings of the
Brunn Society for the Study of Natural History. Mendel did not get
any attention except a commending article in the local newspaper.
Starting in 1866, for four years, Mendel sent his papers and his
ideas to Karl-Wilhelm Ngeli, professor of botany in Munich. Yet,
Ngeli could not see the revolutionary ideas being unfolded before
his eyes. Though Mendels paper was sent to over 120 libraries
around the world, it received scant attention and soon forgotten.
Had they been discovered, Mendels ideas would have revolutionized
the biology of that time. Probably disappointed, in 1868, Mendel
left his beloved garden and was promoted to Abbott a year later.
His increas-ing administrative duties brought an end to his
teaching and his genetics experiments. He died on January 6, 1884
at the age of 61 due to chronic nephritis, unrecognized for his
contribution to science.
Rediscovery of Mendels Laws At the turn of the century, three
botanists, Hugo De Vries (1848-1935), Carl Correns (1864-1933), and
Erich von Tschermak (1871-1962), independently rediscovered Mendels
work on pea plants. The rediscovery of Mendels work led to major
advances in the science of heredity. Soon, it was discovered that
Mendels her-itable factors are genes, and different versions of the
same gene are called alleles. Mendelian laws of genetics apply to
most organisms, including humans. However, not all inheritance
follows the Mendelian ratios, for
Mendels Law of Segregation
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example ABO blood groups. With the advances in imaging
technology, modern genetics made very important strides in the next
de-cades. By the 1940s scientists found out that genes are packed
into a molecule called DNA. In 1944, Av-ery, MacLeod, and McCarty
identified DNA as the hereditary material. In 1953, Watson and
Crick deduced the double-helical structure of DNA with base pairs
A-T and G-C between strands. In 1956, the number of chromosomes in
human beings was determined to be 46. There are 22 pairs of
autosomes and one pair of sex chromosomes. The full set of human
chromosomes is called the karyotype. The normal human karyotype is
46,XY for male or 46,XX for females. In 1970 and 1980s bold
initiatives such as human gene mapping stud-ies were conceived. In
1990 the Human Genome Project was started as a joint effort by the
National Institutes of Health and the Department of Energy. By
April 2003, the complete sequence of the human genome was
announced. The overall size of the genome is about 3.2 billion base
pairs. Despite exaggerated predictions, a wonderful revelation was
the total number of human genes is in the range of just 20,000 -
25,000. With the discovery of genome, the cell, which is the basic
unit of all living organisms, no longer looked as a blob of liquid,
but recognized as a carrier of genetic information that could fill
thousands of volumes in a library. The human body contains
approximately 100 trillion cells. Inside each cell there is a
nucleus. Inside the nucleus are two complete sets of human genome.
One set of the genome came from the mother and one from the father.
The terminology in genetics could be confusing, but a simple
illustration makes it easy to remember. In his book, Genome: The
Autobiography of a Species in 23 Chapters, Matt Ridley compares the
genome to a book: Imagine that the genome is a book. There are
twenty-three chapters, called CHROMOSOMES. Each chapter contains
several thousand stories, called GENES. Each story is made up of
paragraphs, called EXONS, which are interrupted by
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Double helix structure of DNA, discovered by Watson and Crick in
1953.
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called INTRONS. Each paragraph is made up of words, called
CODONS. Each word is written in letters called BASES. English
language has 26 letters, but genomic language has only 4 letters
(A,C,G and T which stand for Ade-nine, Cytosine, Guanine and
Thymine) written entirely in three-letter words. Since its
discovery, the DNA double helix became one of the great icons of
science in our society, rivaling the atom in its ubiquity in our
culture. DNA symbolizes the immense implications for humanity,
impacting two most important applications of biology to human
welfare - Agriculture and Medicine. Recognizing its enormous
significance, while unveiling human genome, President Bill Clinton
described it as the language in which God created life. On 26 June
2000, with Craig Venter and Francis Collins standing beside him,
Presi-dent Clinton said, Todays announcement represents more than
just an epic-making triumph of science and reason. After all, when
Galileo discovered he could use the tools of mathematics and
mechanics to understand the motion of celestial bodies, he felt, in
the words of one eminent researcher, that he had learned the
language in which God created the universe. Today we are learning
the language in which God created life. We are gaining ever more
awe for the complexity, the beauty, the wonder of Gods most divine
and sacred gift. With this pro-found new knowledge, humankind is on
the verge of gaining immense,new power to heal. Genome science will
have a real impact on all our lives -- and even more, on the lives
of our children. It will revolutionize the diagnosis, prevention
and treatment of most, if not all,human diseases Thus, our
knowledge of genetics began with Gregor Mendel who first lifted the
veil on the genetic code by growing pea plants in the abbey
garden.
Impact of Mendels Work on Darwinism On November 24, 1859 Charles
Darwin published his famous book, On the Origin of Species. In
Darwins time there was no acceptable model of heredity. In fact,
Darwin put forward Lamarcks Law of inheritance of acquired
characteristics as a mechanism for evolution. In January 1868,
Darwin published his book, The Variation of Animals and Plants
under Domestication. In Chapter XXVII of this book, Darwin produced
his Provisional Hypothesis of Pangenesis, a venture to provide a
theory of heredity that would account for the production of huge
numbers of heritable individual differences. The theory stated that
each part of an organism tosses out free and minute atoms of their
contents, that is gemmules. The gemmules reach the reproductive
apparatus, and after multiplication and aggregation, they are
passed on to the next generations. The gemmules are affected by the
direct and indirect influences of the conditions of life, and are
carried to the progeny to cause the offspring to vary in a similar
fashion. Thus, Darwin was involved in exhaustive imagination to
conceptualize gemmules to explain Lamarcks Law of inheritance of
acquired characteristics. A few years earlier, Mendel already came
up with solid evidence for genes through his research on pea
plants. It is a tragedy in the history of science, that Mendels
sophisticated work in genetics went unnoticed at the same time when
Charles Darwins Origin of Species became an instant blockbuster. In
their 1929 book The Science of Life, H. G.Wells, Julian Huxley, and
G.P. Wells noted, that Mendels research dealt chiefly with peas and
arithmetic, not the sort of things that cause excitement and
clamour, and in the confused tumult of
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the nineteenth century evolution controversy, they passed
unnoticed. It has been said, a lie will go round the world while
truth is pulling its boots on. The world celebrated the quasi
science of Charles Darwin and its aftereffects while ignoring the
real scientific work of Gregor Mendel. But as the century drew to a
close, Darwins theory of evolution by natural selection met a
serious blow to its scientific validity with the rediscovery of
Mendels laws of heredity. The two fundamental creeds of Dar-winism
- small variations and natural selection - were questioned and
rejected. Darwin had Lamarcks law of inheritance of acquired
characteristics in his On the Origin of Species. Mendels work in
genetics proved that such acquired characteristics of an organism
are not inheritable to the next generation. Organisms procreate
based on their genetic blueprints rather than environmental
influences. It is curious to note how evolutionists came up with
laws such as Lamarcks Law of Inheritance of ac-quired
characteristics, Ernst Haeckels Law of Biogenesis even though there
was absolutely no scientific evidence to support such laws.
Needless to say, Darwinism soon reached a state of deterioration as
enthusi-asm for the idea evaporated after the turn of the century.
In his book, At the Deathbed of Darwinism (1903) Eberhard Dennert,
Ph.D described the pitiful state of Darwinism at the beginning of
20th century: There was at the time a whole group of enthusiastic
Darwinians among the university professors, Haeck-el leading the
van, who clung to that theory so tenaciously and were so zealous in
propagating it, that for a while it seemed impossible for a young
naturalist to be anything but a Darwinian. Then the inevitable
reaction gradually set in. Darwin himself died, the Darwinians of
the sixties and seventies lost their pristine ardor, and many even
went beyond Darwin. Above all, calm reflection took the place of
excited enthusiasm. As a result it has become more and more
apparent that the past forty years have brought to light nothing
new that is of any value to the cause of Darwinism. This
significant fact has aroused doubts as to whether after all
Darwin-ism can really give a satisfactory explanation of the
genesis of organic forms. The foremost challenge evolutionists
faced at the beginning of last century was what to do with Mendels
theory of inheritance. Biologists such as Paul Kammerer (1880-1926)
still held their belief in Lamarckism. Kammerer was an Austrian
biologist who devoted all his biology experiments to proving
Lamarckian theo-ry of the heritability of acquired characteristics.
He claimed that midwife toads in his experiment developed black
nuptial pads on their feet over the span of just two generations.
He argued that the nuptial pads arose to provide more traction to
the toads during mating process. Kammerer publicized it as an
acquired characteris-tic brought about by adaptation to
environment. Dr. G.K. Noble, Curator of Reptiles at the American
Muse-um of Natural History, analyzed Kammerers experiment and
proved it to be a flimflam. Kammerers fraud was exposed: He
injected India ink into toads feet to give them the appearance of
black nuptial pads. Just six weeks after the indictment by Noble,
Kammerer committed suicide in the forest of Schneeberg. Howev-er,
evolutionists such as Ernest MacBride (1866 - 1940) still supported
Lamarckianism and endorsed Paul Kammerers claims to have
demonstrated Lamarckian inheritance in the midwife toad. In his
1924 book, An Introduction to the study of heredity, MacBride
opined that Mendels own results were a little too good to be true
and denounced the concept of the gene. The whole escapade of
Kammerer-MacBride duo shows how blind belief in evolutionism could
prompt even well educated scientists to engage in chicanery to gain
accep-tance for their views. While Lamarckians lampooned Mendels
work after its rediscovery in 1900, the Darwinian evolutionists
were split into two groups on whether variations were small or
large. A spiteful dispute surfaced between the
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two groups: Mendelians and Biometricians. Mendelians promoted
Mendels theory of heredity and believed in discontinuous evolution
while Biometricians endorsed Darwins theory of natural selection
and maintained that evolution proceeded by natural selection acting
upon small variations. Biometricians realized that the discovery of
Mendels laws of inheritance exposed the fatal flaws in Darwins
theory of natural selection. As the fracas brewed between
Mendelians and Biometricians, Darwins cousin, Francis Galton (1822
- 1911) jumped into the fray. Both sides claimed Galton as one of
their own. However, Galton was engrossed in formulating his social
Darwinian theories in Eugenics. He was interested in whether genius
was heritable and argued that variations had to be large. His
conclusions were based on his study of regression. The world would
soon witness the consequences of Darwins ideas through Galtons
theories through their horrendous manifestation in Hitlers
euthanasia programs and Americas involuntary sterilization of
people who were considered mentally inferior. Biometricians
immersed themselves in saving Darwinism in the wake of the
rediscovery of Mendels the-ory of inheritance. Under the leadership
of Walter Raphael Weldon (1860 - 1906), they founded a new field -
biometry in which statistics was used to argue for evolution
through selection that operate on small, continu-ous variations.
Influential English mathematician and a prominent proponent of
eugenics, Karl Pearson (1857 - 1936) became a spokesman for
Biometricians. Mendelians put forward their own representatives.
William Bateson (1861 - 1926), a former student of Raphael Weldon,
strongly criticized biometricians and took a stand for Mendelism.
He scorned the idea that selection could produce new species. He
coined the term genetics to build a new science of heredity based
on large variations. To the chagrin of believers in Darwinism, the
bitter feud between Biometricians and Men-delians soon led to what
is called eclipse of Darwinism around 1900. At the beginning of
20th century, for a biologist who desire to assemble a theory of
evolution, four basic positions were available. 1. Natural
selection (evolution through adaptive and beneficial random
variations)2. Theistic evolution (evolution through purposeful
variations guided by God) 3. Lamarckism (evolution through
inheritance of acquired characters from one generation to the next)
4. Orthogenesis (evolution through forces originating within the
organisms themselves) Theistic evolution and orthogenesis were
outlawed because of their metaphysical inclinations. Certain
utopian ideologies like communism tried to adopt Lamarckism as the
model of evolution, because unlike Darwinism, Lamarckism is
purposeful and directional. Soviet biologist Trofim Lysenko (1898 -
1976) leads that genre. He rejected Mendelian genetics in favor of
the hybridization theories of Russian horticulturist Ivan Michurin
(1855 - 1935), who equated Mendelian Genetics with Capitalist
propaganda. Undergirded by Sta-lins favor, Lysenkos pseudoscience
culminated in vernalization experiments, notoriously recorded in
history as Lysenko Affair. While the pseudoscience put forward to
save Lamarckism in Russia was Lysenkoism, its counterpart to rescue
Darwinism outside Russia was Mutation theory. In the light of
Mendels laws of inheritance, it did not take much time for
evolutionary biologists to realize that Darwins natural selection
did not have sufficient potential to drive macroevolutionary
transformations. They developed Mutation theory, which is evolution
through variability produced by mutations leading to sudden
appearance of significantly new forms. In con-trast to Lysenkoism,
which rejected Mendel, Darwinian evolutionists, with a crafty
sleight of hand, associated Mendel with large variations. They
minimized the role of selection and put forward evolution through
large
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variations produced by mutations. Hugo de Vries (1848 - 1935)
was a Dutch botanist who introduced the term mutation and developed
a mutation theory of evolution. In 1886 he did experiments on
evening primrose (Oenothera lamarckiana) and produced many new
varieties of the plant. He claimed mutations were responsible for
these suddenly appear-ing variations, even though they were the
result of chromosomal duplication (polyploidy). Then he made a wild
extrapolation from his experiment: Mutations do not just produce
variations within the same species, they also create entirely new
species out of existing species. He published his Mutation Theory
between 1900 and 1903, arguing that species originate as a result
of large-scale changes produced by mutations. Just as Charles
Darwin did in his On the Origin of Species, Hugo de Vries made
extrapolated assumptions of macro-evolutionary transformations,
using examples of microevolution. German botanist Carl Correns
(1864 - 1933) was one of the three men, beside Hugo de Vries and
Carl
Correns, who independently rediscovered Gregor Mendels work on
genetics. He was a student of botanist Karl Ngeli, with whom Mendel
corresponded about his work on pea plants, but who failed to
understand the significance of Mendels work. Carl Correns coined
the term Mendelism, equating Mendels name and work with large
variations that allegedly brought on macroevolutionary changes.
Thus, evolutionary geneticists put the responsibility of
macroevolution on mutations, which are essentially deleterious in
nature. Out of infinite number of dangerous mutations,
evolutionists were able to grab a few mutations such as CCR5 and
sick-le-cell trait, label them as positive mutations and display
them as evidence for macroevolution. As the bitter quarrel between
Mendelians and Biometricians encroached into the halo erected
around Dar-
Hugo de Vries believed variations in evening primrose were
caused by mutations. They were actually caused by chromosomal
duplication.
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winism as solid science, evolutionists resolved to restrain the
infighting. By 1929 R.A.Fisher, Sewall Wright, and J.B.S.Haldane
worked out a theory of evolution to reconcile between Mendelian
inheritance, biometry, and Darwinian selection. English
statistician and evolutionary biologist, Ronald Fisher (1890 -
1962), who is named as the greatest biologist since Darwin by
Richard Dawkins, proposed the gradual change of a single large
population due to selection on many minor variations. In 1930 he
published his theory in The Genetical Theory of Natural Selection.
J.B.S. Haldane (1892 - 1964) was a British evolutionary biologist
who corroborated with Ronald Fisher in the foundation of Population
Genetics. Haldane was the progenitor of the atheist-materialist
brand of evolu-tion that completely stripped Darwinism of any
metaphysical moorings. His evolutionary worldview soon led him to
embrace Leninist, Marxist Communism. Not surprisingly,
atheist-materialists of our generation em-ulate him, such as
Richard Dawkins who popularized Haldane in his 1976 book, The
Selfish Gene. Haldane placed great emphasis on strong selection on
single genes. The third key figure in population genetics that
reconciled genetics and evolution was American geneticist Sewall
Wright (1889 - 1988). He argued that adaptation would be most
effective if species were subdivided into many small
subpopulations. Despite these differences, all three founders of
population genetics were quickly embraced by evolutionists because
they were able to contain the damage done to idea of evolution due
to bitter rivalry between Mendelians and Biometricians.
God in Mendels Life From Mendels peas to Double Helices, the
science of genetics rose amazingly. God used one of his own
servants to reveal the language in which he coded the physical
structure of human beings and all other living organisms. Georges
Cuvier (1769 - 1832) the founder of paleontology rejected the idea
of evolution, but evolutionists still believe that fossils support
evolution. Similarly, Gregor Mendel, the founder of modern genetics
rejected the idea of Darwinism, but evolutionists still believe
that genes drive evolution. In fact, they went as far as equating
Mendel with large variations, necessary for macroevolution. Because
of their commit-ment to naturalism and materialism, no amount of
evidence would convince evolutionists of the illogical and
unscientific nature of their belief in Darwinism. Some have argued
that Mendel first joined the monastery not for religious reasons
but because he was struggling to afford his university tuition
(NNDB). They opined that the nature of Mendels research indicates
that he supported evolutionary theories and opposed creationist
hypotheses about the origins of life on earth. However, his work
with plant breeding was actually commissioned and supported by the
church (Sant). Furthermore, although Mendel read Darwins research,
he did not believe in his evolutionary theories. Mendel never
diverted from believing that God was the creator of the world, and
asserted that there was no way creation occurred by blind chance
(Graves). Mendel aimed to glorify God through his scientific
pursuits (Nosotro).
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Bibliography
Barton, Nicholas H. Evolution. CSHL PressBowler, Peter. The
Eclipse of Darwinism, JHU Press, 1992 Graves, Dan. Gregor Mendel.
Scientists of Faith. Kregel Resources: Grand Rapids, MI (1996).
http://www.adherents.
com/people/pm/Gregor_Mendel.html.Henig, The Monk in the Garden:
The Lost and Found Genius of Gregor Mendel, the Father of Genetics.
Lewis, Ricki. Human Genetics: The Basics, Routledge, 2010 McConkey,
Edwin. How the Human Genome Works (Sudbury, MA: Jones and Bartlett,
2004).Nosotro, Rit. Gregor Mendel.
http://hyperhistory.net/apwh/bios/b2mendel.htmNNDB. Gregor Mendel.
http://www.nndb.com/people/015/000083763/ Pierce, Benjamin.
Genetics: A Conceptual Approach (New York: W.H. Freeman and Co.,
2005), Chapter 3. Provine, William B. The Origins of Theoretical
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http://www.asa3.org/ASA/PSCF/1985/JASA12-85Seeger3.html.http://partners.nytimes.com/library/national/science/062700sci-genome.htmlhttp://www.ornl.gov/sci/techresources/Human_Genome/project/clinton2.shtmlThe
Origins of Theoretical Population Genetics: With a New Afterword
(University of Chicago Press)
Paul Kattupalli MD is a physician and author. He can be reached
at [email protected].
God & Science Foundation Inc, May
2013www.godandsciences.org