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Unformatted text preview: Clicker Question Clicker In the developing embryo, the fallopian tubes, In uterus and upper vagina develop from the uterus A) ovaries. B) Wolffian ducts. C) Mullerian ducts. D) Freudian ducts. E) labioscrotal swelling. Where are we? Where I have been discussing reproductive anatomy and have physiology in terms of “I am my genes”. physiology Today we will talk about DNA, the chemical that Today DNA the makes up the genes. DNA is the hereditary genes DNA material traditionally transferred from the male to material the female during sexual intercourse and transferred at conception, from the parents to the offspring. Does our DNA determine who we really really are? are? In the next series of lectures, I hope to help you In “prepare your mind” so that you can critically and deeply think about the influence of DNA on your future as a person. your Maupertuis (1753) Postulated that the Hereditary Material is Particulate Hereditary “If there are, in each of the If seminal seeds, particles particles predetermined to form the heart, the head, the entrails, the arms and the legs, if these particular particles had a special attraction for those which are to be their immediate neighbors in the animal body, this would lead to the formation of the fetus.” Robert Brown Serendipitously Discovered the Nucleus in 1831 while Studying Pollination Studying Nuclei in Orchid Epidermis Taken with Brown’s Microscope with Mathias Schleiden and Theodor Schwann: Promoters of the Cell Theory Schwann: Mathias Schleiden (1838) Mathias speculated that the nucleus was important for the formation of cells in plants. Schleiden’s idea attracted Schleiden’s the attention of a zoologist named Theodor Schwann who promoted the idea that the nucleus was as important in determining the development and morphology of animals as it was in plants. it The Nucleus Is Present in All Cells The The fact that a nucleus is The present in all plant and animal cells was not obvious until Theodor Hartig (1854) and Lord Osborne (1857) developed a stain made of carmine, which comes from the crushed bodies of Mexican cochineal insects. The nucleus then took on a new importance. new The Discovery of Nuclein The Friedrich Miescher Friedrich (1868) was a physician who became interested in investigating the chemical composition of nuclei. nuclei He isolated a He compound from the nuclei of pus cells pus that came from used bandages obtained from a hospital. The Chemistry of Nuclein The When Miescher removed When the fat from pus cells (white blood cells) with alcohol and removed the protein with pepsin-containing pig gastric mucosa, gastric something still remained in the nuclei. He called the new He compound, which contained carbon, nitrogen and phosphorus, nuclein. He phosphorus nuclein He determined that nuclein had the following chemical formula, C29H49N9P3O22. formula, The Chemical Basis of Identity? The • In a speculative note submitted In along with his other work Miescher (1869) suggested that the study of individual nucleins may reveal something about the differences between members of a group. members • However, the idea that one’s However, identity could have a identity chemical basis was beyond chemical belief and the note was rejected by the journal. rejected Visualizing Cell Reproduction Visualizing • About the same time, Eduard Flemming and About others stained cells and watched how the colored material (chromatin) iin the nucleus split n colored into many bodies. • He saw that the nucleus went through a He complicated process (mitosis) to divide the complicated to chromosomes in such a way that each somatic cell had not only the same number of chromosomes, but identical copies of the chromosomes. chromosomes. • During the formation of gametes, a special During division (meiosis) occurred, which resulted in a division occurred, halving (haploid) of the number of halving of chromosomes. During fertilization, the diploid fertilization the number of chromosomes was restored. chromosomes This led to the idea that the chromosomes This contained the self-perpetuating particulate information necessary to build an organism. information E. B. Wilson E. B. Wilson (1895) wrote about the possible function of chromatin and nuclein: chromatin “The precise equivalence of the chromosomes contributed The by the two sexes is a physical correlative of the fact that the two sexes play… equal parts in hereditary transmission, and it seems to show that the chromosomal substance, the chromatin, is to be regarded as the physical basis of inheritance. Now, chromatin is known physical Now, to be closely similar to… a substance known as nuclein nuclein (C29H49N9P3O22, according to Miescher), which analysis (C according shows to be a tolerably definite chemical composed of nucleic acid (a complex organic acid rich in phosphorous) and albumin. And thus we reach the remarkable conclusion that inheritance may, perhaps, be effected by the physical transmission of a particular chemical compound from parent to offspring.” compound Emil Fischer: Synthetic Chemist Emil Reading Emil Fischer’s Reading Nobel Prize acceptance speech gives one an idea of how a chemist or chemical biologist thinks. If one can use uric acid If from guano to make caffeine, why not use it to form the nitrogenous bases of DNA and inject it in people to induce desired genetic traits? desired Emil Fischer (1902) P-urine Emil “Currently the name "purines" is a generic term for a large class of nitrogenous organic compounds, some being certain animal excretions and others the active constituents of important stimulating beverages. The oldest member of the group is known by the rather unattractive name of uric acid and was discovered…as a constituent of… urine. …the enlightened farmer knows it to be a valuable constituent of guano.” “To this end I would ask you to glance at the accompanying set of formulae....” “It will readily be seen on comparing these formulae that they contain a common atomic group, a nucleus as it is called and which I have termed the purine nucleus.” “The simplest combination of this skeleton is … purine…., Replacing a hydrogen atom in purine by the amide NH, forms adenine, and if a further oxygen atom is added, the result is guanine. Lastly, the nitrogen atoms in vegetable products are also linked with the CH3 or methyl group.” “To determine the structure of the molecule the chemist proceeds in a similar way to the anatomist. By chemical actions he breaks the system down into its components and continues with this division until familiar substances emerge [and] the structure of the original system can be inferred from the decomposition products. Usually…the structure will only be finally elucidated by the reverse method, by building up the molecule from the decomposition products or similar substances, i.e. by what is termed synthesis [and] it has become possible to synthesize them all from the inexpensive uric acid….” “Among the purine substances there are two valued drugs, caffeine and theobromine, which so far had to be prepared by extraction from tea and cocoa…. Now that these drugs can be made synthetically from inexpensive uric acid the mind readily turns to exploiting the synthesis on an industrial scale….” “It is even possible to produce the true aroma of coffee or tea artificially, too, by synthesis; with the exercise of a little imagination the day can be foreseen when beans will no longer be required to make good coffee….The layman usually receives with skepticism such prophecies by the chemist and in this specific instance his skepticism will not be weakened by the knowledge that a constituent of guano would be used to prepare the synthetic drink.” “In our age, however, such prejudices on the part of the public do not normally persist for very long. Who, nowadays, still considers that the magnificent dyes colouring our garments and furnishings are derived from unsightly coal tar, or that sweet-tasting saccharin is prepared from the same material ? The point is that chemical transformations are so thorough that the endproduct retains nothing at all of the properties of the original substance. The manufacture of caffeine from uric acid is therefore nothing worse than the processes which occur when manure used to nourish plants is converted into appetizing fruits or into wonderfully scented flowers.” Twinkies: An Partially Synthesized Food Twinkies contain flour, sugar, salt, Twinkies baking soda, water and a trace of egg. baking THE FILLING also includes Partially hydrogenated vegetable oil is the main ingredient. Polysorbate 60 is a gooey substance that helps replace cream and eggs and is derived from corn, palm oil and petroleum. Cellulose gum gives the crème filling a smooth, slippery feel. Artificial vanillin is synthesized in petrochemical plants. petrochemical THE CAKE also includes Lecithin is an emulsifier made from soy. Diacetyl mimics the taste of butter. Yellow No. 5, Red No. 40 give the cake the golden look of eggs. Sorbic acid, the only actual preservative Sorbic in Twinkies, comes from petroleum. in Synthesizing Genes Synthesizing The possibility of testing the hypothesis that nucleic acids The were the genetic material seemed possible to Emil Fischer (1914). He wrote, “With the synthetic approaches to this group we are now With capable of obtaining numerous compounds that resemble, more or less, natural nucleic acids. How will they affect living organisms? Will they be rejected or metabolized or will they participate in the construction of the cell nucleus? Only the experiment will give us the answer. I am bold enough to hope that, given the right conditions, the latter may happen and that artificial nucleic acids may be assimilated without degradation of the molecule. Such assimilated incorporation should lead to profound changes of the organism, resembling perhaps permanent changes or mutations as they have been observed before in nature.” nature Organic Chemists Degraded Nucleic Acids in Order to Determine Their Structures Structures At the turn of the century, nucleic At acids were isolated from wheat germ, yeast and calf thymus in order to study their structures. These studies were based on the These perspectives of organic chemists, including Walter Jones and Phoebus Levene (→), who had a Phoebus ), reductionist approach. reductionist Based on their degradation Based studies, the organic chemists studies the considered nucleic acids to be simple macromolecules. Nucleic Acids Are Composed of Purines and Pyrimidines Purines When nucleic acids were When hydrolyzed, they were hydrolyzed they broken down into their component parts which turned out to be the purines, adenine and purines adenine guanine as well as a guanine new class of compounds known as pyrimidines, cytosine, thymine and cytosine, and uracil. uracil Emergent Properties Emergent The organic chemists made outstanding The contributions to understanding the components of nucleic acids. components However, they lost sight of the fact that the However, parent molecule was a macromolecule, macromolecule and may have a level of complexity that and complexity was greater than the complexity of its component parts. component That is, they did not have the prepared That minds to realize that the parent molecule minds may have emergent properties. emergent Limits to the Reductionist Perspective of Chemists Perspective The chemists developed extraction procedures The extraction that were suitable for degradation studies, but degradation but would not allow them to isolate the native molecule, and to reconstruct correctly the structure of the nucleic acids. Anatomists have the advantage of knowing a priori that their tissue priori slices come from a complex organism. slices The organic chemists did not even consider the The possibility that nucleic acids were complex selfcomplex perpetuating information bearing molecules. In In fact, due to the high number of acidic groups, the nucleic acids were naively considered by chemists to act as pH buffers in the nucleus. to Only Two Kinds of Nucleic Acids Only The nucleic acids seemed to be relatively simple The molecules. Consequently, the approach used to isolate nucleic acids, followed the approach used to isolate other simple materials, and work focused on isolating nucleic acids from a few convenient sources. There was one odd fact though: The nucleic acids of plants seemed to be composed of ribonucleosides while those of animals were composed of deoxyribonucleosides, and Walter Jones deoxyribonucleosides and (1920) concluded in his monograph on nucleic acids, that (1920) "...there are but two nucleic acids in nature, one obtainable from the nuclei of animal cells, and the other from the nuclei of plant cells." other Yeast Nucleic Acid and Thymonucleic Acid Yeast Thus plant nucleic acids were Thus known as either “yeast nucleic acid” or ribonucleic acid, and animal ribonucleic and nucleic acids were known as “thymonucleic acid” or desoxyribonucleic acid. desoxyribonucleic The chemist’s interpretations of the The simplicity of nucleic acids resulted from their preconceived notions preconceived of the simplicity of nucleic acids, and thus they developed inadequate extraction procedures. procedures Conclusion: Nucleic Acids were Simple Molecules Molecules Phoebus Levene (1921) Phoebus concluded that nucleic acids were composed of repeating units of four nucleotides. units According to the According tetranucleotide hypothesis, tetranucleotide the structure of thymonucleic acid was ATCGATCGATCG... acid The tetranucleotide The hypothesis, introduced in 1921 dominated the thinking of scientists for more than twenty years. The technique of X-ray diffraction was proposed by X-ray Max von Laue (1915) and developed by Lawrence and William Bragg (1922,1924) to determine the arrangement of atoms in molecules. William T. arrangement William Astbury (1938) first used X-ray diffraction to determine the structure of DNA. structure X-ray Diffraction of DNA X-ray The X-ray data obtained by The Astbury and Bell (1938) indicated regular repeats regular every 0.33-0.34 nm which they believed were due to the nucleotides, and a 2.7 nm repeat which they believed indicated that the DNA molecule was composed of a repeating sequence of 8 or 16 sequence nucleotides. Perfection of X-ray image Suggests that DNA is Too Simple to be the Genetic Material Material Astbury (1947) concluded: "It seems Astbury improbable, too, to judge by the degree of perfection of the X-ray fibre diagram that these four different kinds of nucleotides are distributed simply at random.“ distributed A nonuniform arrangement of nucleotides would be necessary if the nucleic acids were to function as the genetic material. genetic DNA as the Genetic Material? DNA There was little reason There to even think that nucleic acid was the genetic material based on studies by organic chemists. In fact, Wendell Stanley In (1935) thought that he thought crystallized the hereditary component of the tobacco mosaic virus when he crystallized its protein. Feulgen Stain Shows Plants Also Have DNA DNA But, cytologists were obtaining data that But, conflicted with those of the organic chemists. Using a stain now known as Feulgen’s reagent, Feulgen (1924) discovered that DNA occurred in the nuclei of plants and animals, and not just in those of animal cells. He wrote: just “This gave us great surprise, for the This nuclei of the wheat embryo gave the nucleal reaction more intensively than we have ever seen in any animal tissues…. The old dualism of yeast and thymonucleic acids is thus set aside....” aside....” DNA Content of Nuclei in a Given Organism is Constant Conclusions about the importance of Conclusions DNA based on Feulgen staining were not looked upon favorably because the staining of various cells in the same organism seemed to vary in an unreasonable manner. Approximately two decades later Approximately Alfred Mirsky and Hans Ris (1948,1949) determined that the DNA content of nuclei from somatic cells of the same somatic organism is constant, and organism and variations in the ratio of DNA to protein in the nucleus accounted for the variations in the staining. the A Return to Thinking about DNA as an Information-Bearing Molecule an The chemistry of nucleic acids The went through a revolution when Erwin Chargaff (→), “a licensed Erwin ), biochemist” became aware of the genetic evidence that DNA was the hereditary material. Chargaff was instantly Chargaff captivated by the experiments performed by Oswald Avery, Colin MacLeod and Maclyn McCarty in 1944, which indicated that DNA was the genetic material. genetic Fred Griffith’s Transformation Experiment Experiment Avery’s experiments were Avery’s based on the observations of Fred Griffith, who died in his Fred who laboratory when London was bombed during WWII. Griffith (1928) discovered Griffith that when mice were injected with virulent pneumococci (smooth) that had been heat (smooth) killed, along with live avirulent pneumococci (rough), the mice died of (rough), pneumonia and their blood pneumonia contained living virulent pneumococci. pneumococci. Pneumococci and Pneumonia Pneumococci Smooth bacteria kill mice. They are virulent. Rough bacteria do not. They are avirulent. Heat-killed Heat-killed smooth (virulent) smooth bacteria do not kill mice. kill Live rough Live rough (avirulent) bacteria and dead smooth smooth (virulent) bacteria mixed together do kill mice. do Transformation Transformation Something from virulent bacteria Something transforms avirulent bacteria and makes them virulent. them Dawson and Sia (1931) found that the Dawson transformation of avirulent to virulent transformation pneumatococci could also take place in a test tube outside of a mouse. test Avery et al. (1944) interpreted all of these results Avery to mean that there was a transfer of genetic material between the virulent and avirulent material bacteria during transformation. Avery et al. (1944) wrote: wrote: “Biologists have long attempted by chemical Biologists means to induce in higher organisms predictable and specific changes which…could be transmitted…as hereditary characters. Among microorganisms the most striking example of inheritable and specific alterations…that can be experimentally induced and are reproducible under well defined and adequately controlled conditions is the transformation of… conditions Pneumatococcus.” Transformation: A Transfer of Genetic Material Genetic Chemical Fractionation Shows that the Transforming Factor is DNA the Avery et al. (1944) Avery fractionated the pneumatocci and meticulously isolated the various fractions and found that the transforming principle was none principle other than the proteinproteinfree DNA fraction. Erwin Chargaff: Prepared Mind Erwin Hearing of Avery’s results and believing that DNA Hearing was the genetic material, Chargaff began isolating DNA in earnest. He developed the techniques necessary to isolate gently intact macromolecules of DNA and do quantitative work. Chargaff (1950) “...started in our work from the Chargaff assumption that nucleic acids were complicated and intricate high-polymers, comparable in this respect to the proteins, and that the determination of their structures and their structural differences would require the development of methods suitable for the precise analysis of all constituents of nucleic acids prepared from a large number of different cell types." different Erwin Chargaff: DNA is Complicated Enough to Carry Hereditary Information Carry I cannot stress enough how important it cannot was to approach DNA from the mind set that it may be a complicated, information containing molecule. Chargaff showed that contrary to the Chargaff prediction of the tetranucleotide hypothesis, adenine, guanine, cytosine and thymine were not present in equimolar amounts in DNA, and the proportions of nucleotides differed in the DNA from different species. Chargaff (1950) further observed, "It is, Chargaff however, noteworthy...that in all the deoxypentose nucleic acids examined thus far the molar ratios of total purines to total pyrimidines, and also of adenine to thymine and of guanine to cytosine, were not far from 1." not Rosalind Franklin and X-ray Diffraction Diffraction While Chargaff was While working on the chemical nature of DNA and finding that each individual has different DNA molecules, Rosalind Franklin was Rosalind using X-ray diffraction to determine the physical structure of DNA. structure Calf Thymus and X-ray Diffraction Pattern of Calf Thymus DNA Pattern Quantum Mechanical Model of DNA At the same time Linus Pauling At Linus and Robert Corey (1953) were working on the structure of DNA from the perspective of theoretical physics. They had already been They successful in applying the concepts of quantum mechanics and the importance mechanics of hydrogen bonding to hydrogen determine the structure of proteins. proteins They were now utilizing this They same approach to deduce the structure of DNA. structure Linus Pauling (December 31,1952) Linus “The nucleic acids, as The constituents of living organisms, are comparable in importance to the proteins. There is evidence that they are involved in the processes of cell division and growth, that they participate in the transmission of hereditary characters, and that they are characters and important constituents of viruses. An understanding of the molecular structure of the nucleic acids should be of value in the effort to understand the fundamental phenomena of life.” phenomena The Triple Helix The Pauling and Pauling Corey came up with a model of DNA that could best be described as a triple helix, triple with the purine and pyrimidine bases pointing out. out Linus Pauling Linus Pauling had planned to visit Rosalind Franklin to see if her data would confirm or refute his model, but he was not issued a passport by the State Department due to his liberal politics and concern about the ill effects of nuclear fallout. Linus Pauling later won the Nobel Prize in Chemistry in 1954 and the Nobel Peace Prize in 1962 Nobel Lack of Integrity: James Watson and Francis Crick Francis Unbeknownst to Rosalind Unbeknownst Franklin, James Watson and Francis Crick did see a report of her unpublished results, and unpublished rushed to publish an a posteriori model of DNA posteriori that synthesized Avery et al.’s genetic data, Chargaff’s chemical data, and the physical data obtained by Franklin without any acknowledgement. Genetic Twoness in the Double Helix Genetic The X-ray diffraction The images taken by Franklin were excellent, and, when the DNA was observed in certain conditions of hydration, the images could only be interpreted to result from a structure that has a double helix. double Twoness Makes Sense in Terms of Genetic Replication Genetic The double nature was The double beautiful from a biological and genetic perspective. perspective. Watson and Crick Watson (1953) saw this and wrote, “It has not escaped our notice that the specific pairing we specific have postulated immediately suggests a possible copying mechanism for the genetic material. genetic Chemistry of DNA Nitrogen Bases Nitrogen The Double Helix The Athena Arose from the Head of Zeus Athena From reading their 1953 paper, it From would seem that the double helix sprung out of Watson and Crick’s heads just like Athena sprung from the head of Zeus. Indeed it even seems like the whole field of molecular biology started with the publication of their paper. I hope that I have shown, that this discovery like most discoveries in biology involve the work of many people. Unlike other many Unlike discoveries, this one has stimulated many people involved in the discovery to question the ethics of James Watson. ethics The Human Genome Project The Watson is a man who Watson contemplates ethical issues himself. He helped launch the human genome project, a llarge-scale arge-scale project initiative, involved in sequencing the entire human genome, in order to better the human condition. The use of genetics to better the human condition is known as eugenics. eugenics In an autobiographical article entitled, “Values from a Chicago Upbringing”, Watson (1995) wrote of the importance of the human genome project and eugenics: “But diabolical as Hitler was, and I don’t want to minimize the evil he perpetuated using false genetic arguments, we should not be held in hostage to his awful past. For the genetic dice will continue to inflict cruel fates on all too many individuals and their families who do not deserve this damnation. Decency demands that someone must rescue them from genetic hells. If we don’t play God, who will?” play Using DNA to Better Society Using • James Watson published a model of the structure of DNA based on what could be considered to be an unscrupulous use of someone else’s data and was awarded the Nobel Prize for it. the • He is interested in making He society better by playing society God. God • He said that Africans are less He intelligent than Westerners. Because of this statement, he is now the former Chancellor former of Cold Spring Harbor Laboratory. Laboratory Harry Laughlin and Charles Davenport of Cold Springs Harbor also wanted to use genetics to better society genetics Eugenics: The Self Direction of Human Evolution Human Eugenics Record Office; Cold Spring Harbor, New York (1910-1939) Harbor, Eugenics Record Office; Cold Spring Harbor, New York (1898-1939) Harbor, Eugenics Record Office Eugenics http://www.eugenicsarchive.org/eugenics/ Charles B. Davenport: Eugenics Charles “Eugenics is the science of the Eugenics improvement of the human race by better breeding or, as the late by Sir Francis Galton expressed it: -‘The science that deals with all influences that improve the inborn qualities of a race.’ The eugenical standpoint is that of the agriculturalist who, while recognizing the value of culture, believes that permanent advance is to be made only by securing the best ‘blood’. Man is an organism—an animal; and the laws of improvement of corn and of race horses hold true for him also.” for Why Take Care of the In-Valids When We Can Eliminate Them? We “The human babies born each The year constitute the world’s most valuable crop. Take the valuable population of the globe to be one and one-half billion, probably about 50 million children are born each year….It is a reproach to our intelligence that we as a people, proud in other respects of our control of nature, should have to control should support about half a million insane, feeble-minded, epileptic, blind and deaf, 80,000 prisoners and 100,000 paupers at a cost of over 100 million dollars a year.” 100 To Charles B. Davenport, Diversity Was Not a Good Thing Was “When we look among our When acquaintances we are struck by their diversity in physical, mental, diversity and moral traits. Some of them have black hair, others brown, yellow, flaxen, or red. The eyes may be either blue, green, or brown; the hair straight or curly; noses long, short, narrow, broad, straight, aquiline, or pug. They may be liable to colds or resistant; with weak digestion or strong. Their hearing may be quick or dull, sight keen or poor, mathematical ability great or small.” great Diversity Provides the Basis for Improving the Human Harvest Improving “The disposition may be cheerful or melancholic; The they may be selfish or altruistic, conscientious or liable to shirk. It is just the fact of diversity of characteristics of people that gives basis for the belief in the practicability of improving the qualities of the ‘human harvest’….The method qualities The of inheritance of these characteristics is not always so simple….The element of inheritance is not the individual as a whole or even, in many cases, the traits as they are commonly recognized but, on the contrary, certain unit characters. What are, indeed, units and what are complexes it is not always easy to determine and it can be determined only by the results of breeding.” determined Marriage is an Experiment in Human Breeding Breeding “To get at the facts it is necessary to study the To progeny of human marriages. Now marriage can be and is looked at from many points of view. In novels, as the climax of human courtship; in law, largely as a union of two lines of property-descent; in society, as fixing a certain status; but in eugenics, which considers its biological aspect, marriage is an experiment in breeding; and the children, in their varied combinations of characters, give the result of the experiment. characters, That marriage should still be only an experiment in breeding, while the breeding of many animals and plants has been reduced to a science, is ground for reproach.” science, Look at Humans the Way we Look at GuineaLook Pigs, Chicken, Wheat and Cotton “Surely the human product Surely is superior to that of poultry; and as we may now predict with precision the characters of the offspring of a particular pair of pedigreed poultry so may it sometime be with man. As we now know how to make almost any desired combination of the characters of guinea-pigs, chickens, wheats, and cottons so may we hope to do with man.” do Criminality is a Hereditable Dysgenic Trait Criminality According to Davenport (1911), According poverty is a bad genetic (dysgenic) hereditable trait. (dysgenic) Richard Dugdale (1877), a Richard sociologist, did a study on the “Jukes”, a clan from the Hudson clan Valley of 700 criminals, prostitutes, and paupers descended from "Margaret, the Mother of Criminals.” A.H. Estabrook, of the Eugenics A.H. Record Office, continued to study the “Jukes” (1915) and found unrelenting hereditary evidence that criminality was a dysgenic trait. dysgenic Feeblemindedness is a Hereditable Dysgenic Trait Dysgenic By studying the “Kallikaks”, By Henry H. Goddard also found unrelenting hereditary evidence that feeblemindedness was also feeblemindedness a hereditable dysgenic trait. dysgenic The dysgenic gene entered The the family when Martin. Kallikak Sr., a Revolutionary War hero had a tryst with a barmaid who carried the feebleminded gene. From then on, feeblemindedness ran in that line in the Kallikak family. family. The Kallikaks Dysgenic Traits Can Enter the Population through Immigration Population According to Charles Davenport, Jewish Immigrants Are Bringing these Bad Traits to America America “There is no question that, taken as a whole, the There hordes of Jews that are now coming to us from Russia and the extreme southeast of Europe, with their intense individualism and ideals of gain at the cost of any interest, represent the opposite extreme from the early English and the more recent Scandinavian immigration with their ideals of community life in the open country, advancement by the sweat of the brow, and the uprearing of families in the fear of God and the love of country.” love Immigrants Will Change the Population of America for the Worse of “…iit appears certain that, unless conditions t change of themselves or are radically changed, the population of the United States will, on the account of the great influx of blood from Southaccount eastern Europe, rapidly become darker in eastern pigmentation…. Since of the insane in [public] hospitals there are relatively more foreign-born than native it seems probable that, under present conditions, the ratio of insanity in the population will rapidly increase.” population Books About Immigrant Scientists Who Were Not Insane, Including Einstein, Fermi, Bethe, Salpeter, Haber, Krebs, Djerassi Bethe, Davenport’s Recommendation Davenport’s “If increasing attention is paid to If the selective elimination at our ports of entry of the actually undesirable (those with a given germ plasm that has imbecile, epileptic, insane, criminalistic, alcoholic, and sexually immoral tendencies); if agents in Europe learn the family history of all applicants for naturalization;… then we may expect to see our population not harmed but improved by this mixture with a more mercurial people.” more www.museumofdisability.org New York Times October 22, 1913 New York Times February 27, 1914 The Great Race The According to Madison Grant, a According trustee of the American Museum of Natural History, the Nordic, Germanic and white Anglo-Saxon Protestants had the best genes or eugenes best since they could tolerate the cold climates of the North. cold By extension, people from By warmer climates, who had only entered the colder climates to get jobs created by the brilliant creators of the industrial revolution, had inferior genes inferior (dysgenes). Madison Grant: Author of “The Passing of the Great Race” Passing “The days of the Civil War and The the provincial sentimentalism which governed or misgoverned our public opinion are past, and this generation must completely repudiate the proud boast of our fathers that they acknowledged no distinction in ‘race, creed, or color,’ or else the native American must turn the page of history and write: of ‘FINIS AMERICAE’” Osborn (1905) Discovered T. rex Osborn Henry Fairfield Osborn: In the Preface to The Passing of the Great Race by Madison Grant Race “…the author…has turned this historical sketch the into the current of a great biological movement, biological which may be traced back to the teachings of Galton and Weismann….This movement has compelled us to recognize the superior force and stability of heredity, as being more enduring and stability as potent than environment. This movement…proves that environment and in the case of man education have an immediate, apparent and temporary influence, while heredity has a deep, subtle and permanent influence on the actions of man.” permanent Henry Fairfield Osborn Henry “What is the greatest danger What which threatens the American republic to-day? I would certainly reply: The gradual dying out among our people of those hereditary traits through which the principles of our religious, political and social foundations were laid down and their insidious replacement by traits of less noble character.” noble The Character of a Nation…. The Harry Laughlin, the Director of Harry the Eugenics Record Office, testified to the Congressional Committee on Immigration and Naturalization in 1922, “The The character of a nation is determined primarily by its racial qualities; that is, by the hereditary physical, mental and moral or temperamental traits of its people.” people.” The proportion of Russians, Jews and Italians in The public insane asylums is greater than their proportion public in the population. in Therefore immigrants from Eastern and Southern Therefore Europe have inferior genes and should not be allowed into the country. He neglected to consider the possibility that the He immigrants were in the public institutions because they were not wealthy enough to be in the private asylums along with the insane long-time Americans. asylums Laughlin was considered to be the expert witness to Laughlin the committee that crafted the Immigration Act of 1924, which aimed at maintaining the same racial 1924 which composition that existed in 1890, before there was a large influx of immigrants. large Return the US to the Racial Composition Prior to 1890 1890 Immigration Act of 1924 United States Statutes at Large (68th Cong., Sess. I, Chp. United 190, p. 153-169) AN ACT AN To limit the immigration of aliens into the United States, and for other purposes. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That this Act may be cited as the ''Immigration Act of 1924.'' Numerical Limitations. Sec. 11. (a) The annual quota of any nationality shall be 2 Sec. per centum of the number of foreign-born individuals of such nationality resident in continental United States as determined by the United States census of 1890, but the minimum quota of any nationality shall be 100. American Eugenics Influenced Adolf Hitler Hitler In a letter to Madison Grant, Hitler thanked him for writing “The Passing of the Great Race” and said that "the book was his Bible." In 1936, Laughlin was awarded an honorary doctorate of medicine from the University of Heidelberg, the intellectual seat of the Nazi regime. The Admiration was Mutual The The Nazi’s Eliminated Dysgenic Traits in the Gas Chamber in Emergency Repeal of the Immigration Act of 1924? Act In 1934, Congress was In considering the possibility of increasing the quotas to allow in the Jewish refugee children who were fleeing from Hitler’s Nazi Regime. The Committee again called upon Harry Laughlin, since “Mr. Laughlin is beyond Mr. doubt the foremost authority in the United States.” in Laughlin testified that “The Laughlin Jews are no exception….” Jews and the refugee boats were sent away from the ports. sent The Closure of the Eugenics Record Office Office In the late 1930s, the United States became increasingly concerned about its own apparent support of the very scientific principles that Germany used to exterminate the non-Aryans. American medical, scientific and political leaders viewed the Eugenics Record Office at Cold Spring Harbor as an embarrassment. In December 1939, the Carnegie Foundation formally closed the Eugenics Record Office. Do People Use Science to Promote Racist Agendas Today? Racist Will the Human Genome Will Project have any similarities with eugenics? similarities Howard Gardner proposes Howard that scientists enter an ethical covenant stating ethical they have a prepared mind to focus on the possible applications or misapplications of their work. work. http://www.howardgardner.com/Papers/documents/Eth%20Resp%20of%20Sci_Feb-02_HG%20pdf.pdf “We now have discrimination down We to a science.” to “They’ve got you looking so hard for any flaw that after a while that is all you see.” What is a gene? What The cell contains a memory of its past and a The memory potential of its future, and this special aspect of potential and life is inseparable from the DNA. DNA Each gene present in the nucleus is related to the Each first ancestral gene. ancestral The ancestral gene probably followed a “repeat repeat and vary” theme, which allowed a new gene to and theme, accumulate mutations in a selectively-neutral manner until it fulfilled a new selectable function. manner In this way, the ancestral gene has survived in In many forms throughout the genome of an organism and throughout the evolution of life. Genes vs. Traits (Phenotypic Characters) Genes • While some traits depend exclusively on the nucleotide While sequence of a single gene, the majority of traits depend on many factors, including the genetic background in which genetic the gene is expressed and the environment. environment • There is not a one-to-one correspondence between a “gene” and a trait; and when we speak of genes we must specify whether we are speaking about the sequence of DNA or of traits. • As we have seen, there is not a simple relationship As between genes (e.g. sry) and traits (male or female). between • According to Charles Davenport, “…nothing is inherited According except the determiners in the germ cells; the characters themselves, on the contrary, are not directly inherited.” themselves, The Sequence of DNA The • As we will discuss next time, the sequence of the As base pairs of DNA determines the sequence of amino acids in proteins. amino • Clever techniques have been devised by Walter Clever Gilbert (1981) and Frederick Sanger (1981) to determine the sequence of bases in DNA. determine Walter Gilbert is a Reductionist Walter “…that when we that have the complete sequence of the human genome, we will know what it is to be human”. human Can A Human Being Be Reduced to His/Her DNA Sequence? • What determines our What human nature? human • Is our DNA sequence a Is part of our human nature, and if so, how big a part? big • How does gene doping How affect our human nature or our inhuman nature? or Nature via Nurture Nature The distinction between genes The and environment is a false dichotomy. Many genes are dichotomy Many affected by the environment. affected Genes may play a larger role than Genes environment in eye, hair and skin color, number of fingers and toes, the formation of the intestines and pancreas and the enzymes in them. them. Genes also play a large role in the Genes formation of the brain. formation But, do genes play a larger role But, than environment in intelligence, scientific and artistic ability and business acumen? Am I my genes? If so, If I found I had a gene for a disease should I drop If my boyfriend/girlfriend, not marry and not have children? What if it is not such a bad disease? children? Should a boyfriend/girlfriend require a copy of your Should DNA sequence before the first date? DNA Should a college require a copy of your DNA Should sequence along with or instead of your application? application? Should an employer require a copy of your DNA Should sequence along with or instead of your application? application? Should an insurance company require a copy of Should your DNA sequence along with your application? your Have you ever said? Have “My genes made me do that.” “I don’t have the right genes to attempt that.” Designing the Human Genotype Designing Eugenics was a way of perfecting the Eugenics human race by human – sterilizing people with dysgenic traits. – llimiting immigration of people with dysgenic imiting traits. traits. – murdering people with dysgenic traits. – encouraging marriage between people with encouraging eugenic traits. eugenic The New Eugenics or Newgenics is a way The of perfecting the individual by: of – selecting in vitro embryos that have eugenic selecting traits and not dysgenic traits. traits – gene doping with selected human growth gene hormone, insulin-like protein1 and myostatin genes. genes. The New Synthetic Chemistry… And One That Would Look Familiar To Emil Fischer Hate Crimes Hate • We have a history of hating We people because of the genes they got by chance; specifically the genes in epidermal cells that code for the synthesis of melanin. • How will we feel about How people who have genes we don’t like as well as the ability to change their genes? genes? • Let’s acknowledge our Let’s history and do what we can to eliminate hate in the future. future. Ebony and Ivory Ebony ...
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This note was uploaded on 04/04/2009 for the course BIO G 110 taught by Professor Wayne,r. during the Spring '07 term at Cornell.

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