gregor mendel

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1 Modern Genetics began in 1900, with the discovery of Gregor Mendel’s 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. Mendel’s 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 God Dr. Paul Kattupalli

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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 advertisements

    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 Population Genetics: With a New Afterword, University of Chicago

    Press, 2001.Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters (New York: HarperCollins, 2006). Sant, Joseph (2012). Mendel, Darwin and Evolution. Retrieved from http://www.scientus.org/Mendel-Darwin.htmlSeeger, Raymond J., Mendel, Monk. The Journal of the American Scientific Affiliation, 37 (December 1985): 233-

    234. 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