Epigenetics: The Death of the Genetic Theory of Disease Transmission 1st Edition

CHAPTER EIGHT

Darwin and Mendel

In biology, Darwin and Mendel came to define the 19th century as the era of evolution and genetics; Watson and Crick defined the 20th century as the era of DNA (and the double helix), and the functional understanding of how genetics and evolution interact. But in the 21st century it is the new scientific discipline of epigenetics that is unraveling so much of what we took as dogma and rebuilding it in an infinitely more varied, more complex and even more beautiful fashion.

—Nessa Carey, PhD

University of Edinburgh

There was, it is true, a moment early in the twentieth century when it seemed possible that Darwinism might be toppled. As Mendel and his theory of genetics were rediscovered, spread rapidly, and were accepted and enlarged upon, some thought that genetics was incompatible with Darwin. But after the First World War, Ronald Fisher showed that it was possible to reconcile Darwin and Mendel. Indeed, said Fisher, “Mendelism supplied the missing parts of the structure erected by Darwin.” Darwin showed the what of evolution and the why, of natural selection. Now Mendel had produced the how, genetics. This was reinforced when Hermann Joseph Muller showed that genes are artificially mutable. Thanks to Fisher and Muller and others, such as J. B. S. Haldane, by the 1930s, Darwin-Mendelism was triumphant. The way was then open for James Watson and Francis Crick to discover the double helix structure of DNA. So on to the genome and the present infinite possibilities of the science.

—Paul Johnson

Darwin: Portrait of a Genius

All agree that no other scientific theory in history has created as much debate and controversy as Charles Darwin’s theory of evolution. Prior to Darwin’s theory, the prevailing belief was that the planet Earth was 6,000 years old and that the various species on Earth had no relationship to one another. It was thought that humans were unique and superior to all other organisms and that plant and animal physiology had no relationship to human physiology.

The Life and Work of Charles Darwin

Charles Darwin’s paternal grandfather, Erasmus Darwin (1731–1802), finished Cambridge and then trained as a physician in Edinburgh and set up a successful practice in Litchfield. Stories of his skills as a physician reached the court of King George III, who invited him to London to become the royal doctor. Dr. Darwin chose not to accept this offer since he was content with his successful practice and his hobbies of poetry and science. The symbol of Dr. Darwin’s broad interests was his coach, which he personally designed. It contained a writing desk, a skylight, and a portion of his library, thus furthering his intellectual interests while traveling on his professional rounds.

Dr. Erasmus Darwin’s mind was “omnivorous.” He was interested in basic science and he constructed a personal maxim: “Any man who never conducts an experiment is a fool.” He read widely, in French as well as English, and two of his favorite writers were Buffon and Lamarck, who were early supporters of the theory of evolution. He spent time with and wrote frequently with Rousseau. He attended brain storming sessions with industrialists and inventors, including Watt and Boulton, and his deep scientific interests included botany and animal studies.

With success as a physician he was able to purchase a small acreage and planted an eight-acre experimental garden He wrote and published a two-part poem titled The Botanical Garden, covering “The Economy of Vegetation” and “The Loves of the Plants.”

The poem was well received and highly praised by Horace Walpole and translated into French, Italian, and Portuguese. He broadened the readership of his poem in a prose work, Phytologia; or, The Philosophy of Agriculture and Gardening (1799), which is full of speculation concerning the generative life of plants.

It was, however, his report entitled Zoonomia, Or The Laws of Organic Life (1794–96), that is his crowning glory for contributions to science. In it he posited an expanded theory on the age of the earth that was a generation before Charles Lyell’s geological studies established a theoretical geological age, and Darwin theorized accurately on the successive phases of life that emerged and on its “essential unity.” He wrote: “As the earth and ocean were probably peopled with vegetable productions long before the existence of animals, and many families of these animals long before other families of them, shall we conjecture that one and the same kind of living filaments is and has been the cause of all organic life?”

The term “living filament” was a profound utterance in 1794, although surely Erasmus Darwin had probably used the term for many years before he put it to the pen. His use of the term “filament” shows that he was aware of the physical anatomy of the chromosome—as a double helix filament! He had never heard the term “genetics,” but he knew that information was being passed on from one generation to the next.

Erasmus Darwin was married two times and had three sons by his first wife. The first son became a top medical student at Edinburgh but died from an infection received while dissecting in the anatomy laboratory; the second was a flourishing lawyer, but unfortunately committed suicide. The third son, Robert, attended Edinburgh, graduated as a physician and practiced in Shrewsbury, and became one of the wealthiest general practitioners of medicine in England. He was a man who traveled in academic circles and was a Fellow of the Royal Society. This man was the father of Charles Darwin. Erasmus Darwin had four sons and three daughters, His daughter, Violetta, married Tertius Galton and gave birth to Francis Galton, a polymath of genius who designed the science of eugenics.

Eugenics was a concept where one could by “selective breeding” accelerate evolution and produce a race of super humans. This pursuit eventually became a double-edged sword.

Joseph Priestley, one of Erasmus Darwin’s friends, was a minister and theologian described as an Arminian, socinian, and an atheist. He was most widely known for his research as an experimental chemist and as the discoverer of oxygen.

On occasion, Priestley’s writings were publically burned, but his person had never been attacked until the onset of the French Revolution. In a weak, thoughtless moment, he described his political views in Letters, published in 1790, as “Grains of Gunpowder” for which his opponents were “providing the match.” This caused his friends and enemies alike to refer to Priestley as “Gunpowder Priestly.” It was a time of “Constitutional Societies” that were established to support the French Revolution and agitate for similar reforms in England. Conversely, there were Church-and-King organizations created to oppose them.

On July 14, 1791, Priestley was invited to address a meeting in Birmingham to commemorate the anniversary of the Fall of the Bastille. He was warned of the possibility of a personal attack so he turned down the invitation. When they learned that Priestley had cancelled, a Church-and-King mob surrounded his house at Fairhill near Birmingham and burned it, destroying nearly all of his books, scientific apparatus, and papers.

Priestley escaped with his life, however. Order was not restored for three days and four rioters were hanged. Priestley received compensation and supporters helped him resettle in London.

Priestley never felt safe again, and in 1794 he packed all of his belongings and moved to New York. The attack on Priestley and enforced exile of Priestley became a defining event in the Darwin family and in the lives of their dissenting and unorthodox friends.

Charles Darwin was severely affected by this and became more defensive than his grandfather and his father. What terrified Charles Darwin was the religious aspect of the attack on Priestley by the Church-and-King mob. It left Darwin with a high awareness and lifetime fear of the possible results of offending the “tender consciences of Church of England clergymen, who might then be inspired to stir up a mob to burn and kill.”

Tales of the cry of the mob, who were said to have called out “No philosophers—Church and King forever!” and “Burn the atheists!” continued to echo in his mind and fray his nerves. These events contaminated his life and work at a level of concern that had unrelenting consequences.

Dr. Robert Darwin, father of Charles, was a man of strong intellect. The force of his medical skill came from his intuitive penetration during which he used visual and observational powers and probed subjects with pin-pointed questions. Essentially, his diagnostic technique was the same as that used by Dr. Joseph Bell, the famous surgeon who mentored the young physician Arthur Conan Doyle, who went on to create the character of Sherlock Holmes.

Robert Darwin’s genius was inspired by his immediate and personal physical contact with the patient, on the first visit, during the first diagnosis, and which continued on subsequent visits and at every stage of the course of the condition. With these methods Dr. Robert Darwin came to intimately understand disease. It is said that he looked into and through his patients and was able to inspire in them, almost without exception, a confidence in his capacity to cure them in a manner that was widely considered miraculous. After completing his medical studies in Leyden, he began his medical practice at the age of twenty and was an immediate success—his first year’s fees supported a servant and two horses, and his practice grew every year for sixty years.

Dr. Robert Darwin abhorred many of the injurious practices of the medical community, for instance, the use of blistering (topical application of liquid mercury) as well as purging (oral dosing of liquid mercury), and bleeding (bloodletting). In fact he hated the sight of blood, “a horror that he passed on to his son.” It is said that the best doctors in the early nineteenth century were those who physically did least, and Robert Darwin was one of them. As an alternative he provided wisdom and sensibility.

Charles Darwin was born on February 12, 1809, at The Mount in Shrewsbury, the substantial house his father had built. It was “a vintage year for great men— also born were, Tennyson and Gladstone, and Lincoln.” Napoleon cast a giant shadow over Europe and Madison was being inaugurated as the fourth president of the United States.

Charles Darwin had a happy and favored childhood. He loved and respected his father, and he grew up in the magical environs of his father’s house, gardens and fields. His family life was well-organized and many servants pampered him. Darwin was born a gentleman when the term had a social meaning and a legal status as a lord and land holder.

Darwin’s uncle, Josiah Wedgewood II, purchased a 1,000 acre estate at Maer in Staffordshire. This estate was the breeding ground of Darwin’s fascination with riding, shooting, and collecting. The British game laws were strict and rigorously enforced, and one had to be a landholder to shoot wildlife. Darwin’s family status allowed him to shoot and hunt, a practice he greatly enjoyed. Darwin wrote, “I became passionately fond of shooting & I do not believe that anyone could have shown more zeal for the most holy cause than I did for shooting birds.”

Darwin distained cruelty, yet shooting for sport and collection of birds cultivated his interest in science. He dropped hunting as a sport in his early forties, although he continued his hunting to catch, kill, and dissect large numbers of insects, invertebrates, birds, and animals in his thirst for knowledge.

The 1809 news that would have been of the most interest to the adult Darwin was the news that a naturalist and artist, John James Audubon, had successfully banded pewees near Pittsburgh, proving that migratory birds return to nest to the very place where they were hatched.

In 1831 the British naturalist Charles Darwin embarked on his famous voyage on the H.M.S. Beagle that took him around the world for the purpose of documenting and cataloging new species. Darwin returned to England in 1836 and began compiling his observations into a book.

One of his more interesting observations was when Darwin sailed the Beagle to the east coast of South America in 1833. He recorded a fine red dust accumulating on his ship each day and correctly deduced that the dust had originated in west Africa. This African dust in its westerly flight travels all the way to the rainforests in the Amazon where it is essential to the annual replenishment of the rain-leached, mineral-poor soils of the rainforests.

Man has always realized the enormity of the great and tireless power of the earth’s winds; however, their importance to the biological vitality of the earth and the mineral value of our food is far beyond a level that we have ever dreamed. There are many wind currents, east to west, which transport great loads on mineral-laden dust across predictable routes, “linking ecosystems hundreds and even thousands of miles apart.” Billions of tons of mineral-rich dust from the deserts of Asia and Africa fertilize oceans and rainforests halfway around the world. Columbus knew of these winds and used them to drive his ships into the New World, but it was Darwin who knew that the windborne minerals fertilized the world.

Michael Garstang, professor of meteorology at the University of Virginia in Charlottesville, stated, “During the violent Amazonian rainstorms, the particulates that originate in the African deserts are literally sucked out of the sky.” Garstang and his colleagues calculate that 13,000,000 tons of African and Asian mineral-rich dust invigorates the depleted and rain leached Amazonian soils each rainy season.

The wind-borne African dust adds essential minerals to help maintain the rainforests productivity. “While the Amazon Basin teems with life, the soil itself lacks reserves of nutrients, especially phosphates, which spur plant growth. The historical record shows that the Amazon rainforest periodically shrunk to a fraction of its 20th century size, then rebounded again, and the researchers now believe that it expands and contracts as the volume of African dust waxes and wanes with mirror changes in the Sahara Desert.”

When there was a draught in Africa, the resultant dust fertilized and expanded the oceans and the Amazon forests. When there was great rainfall in Africa the reduction in dust volume caused the ocean fauna and the Amazon forests’ biomass to contract.

The observations of numerous individuals in the early 19th century led to a theory that came to be known as the “cell theory”—the idea that cells are the building blocks of all life.

When Germans Matthias Schleiden and Theodor Schwann presented their findings in 1838, the science and practice of biology changed forever.

According to the cell theory, cells are the smallest forms of life and all living organisms are composed of cells. Furthermore, only pre-existing cells can create cells—new cells do not arise spontaneously or come from another source.

Schleiden based his research on the work of Scottish botanist Robert Brown, who had discovered the cell nucleus. It was Schleiden, however, who understood the true importance of the nucleus and its role in the development of the complete cell. At the same time, Schwann was studying animal cells and trying to work out a puzzle: why did certain structures in animal and plant cells look so similar?

It was Schleiden’s observations of the nucleus that gave the biologist the answer. As both plant and animal cells contain a nucleus, Schleiden postulated that cells must be the building blocks of life.

The primary difference between plant and animal cells is that animal cells have flexible walls allowing for malleability and different shapes while plant cells have rigid walls. Also, the chloroplasts in plant cells enable the plants to utilize the sun’s light energy to activate photosynthesis, the process that extracts C02 from the atmosphere to generate carbon chains and carbon-based substances, such as carbohydrates, sugars, vitamins, amino acids, and fatty acids.

Charles Darwin published his life’s work and observations in his book, On the Origin of Species by Means of Natural Selection in 1859 (the title of the sixth edtion of 1872 was changed to The Origin of Species). Darwin surmised that all life on Earth is related by a process of inheritance—a conclusion he arrived at after years of traveling the world studying plants and animals.

Darwin understood that individual organisms vary widely in their capacity to survive and reproduce. An example would be that a sudden drop in environmental temperature occurs, and most individuals of a species die from hypothermia because they can’t tolerate a precipitous drop in temperature. But individuals of that species that can tolerate a rapid drop in temperature survive, reproduce and flourish. As long as the ability to adapt to rapid temperature drops is heritable, the trait is passed on to future generations, and greater numbers of individuals inherit the trait and one variation of the original population will flourish and increase in numbers.

When various populations of a species are separated and isolated by distance or geographical barriers of mountains, rivers, islands, deserts, and so forth, they are faced with a wide and different variety of catastrophic events. After long periods of time, such as decades or centuries, the individuals with common ancestors that have acquired the traits necessary to survive through heritance, will eventually become a separate and distinct subspecies.

Darwin came up with the theory of natural selection. Darwin as a contemporary of Mendel never knew of Mendel and never understood the principals of the science of “genetics,” but he did develop three basic principles that have been confirmed through genetic studies:

1.             Variation is random and unpredictable.

2.             Variation is heritable (able to be transmitted from one generation to the next.) Mendel’s pea research and thousands of genetic studies over the past 100 years have confirmed heritability. Heritable genetic transmission has been confirmed by DNA “fingerprinting” techniques. By using DNA fingerprinting techniques one can trace heritable genetic variation for such things as “paternity testing.”

3.             Variation changes in frequency over time. The Hardy-Weinberg principle codified this concept through the prism of population genetics in the early 1900s. Since the 1970s, genetic studies employing DNA sequencing confirmed that genetic variation within populations changes through mutation and geographic isolation.

The Life and Work of Gregor Mendel

In 1856, in a small walled garden of the Agustinian monastery of St. Thomas in what is now Brno, Czech Republic, the abbot constructed a greenhouse to house experiments in plant breeding. Gregor Mendel, a young teacher who had just returned from studies at the University of Vienna, was appointed to tend the experimental gardens. Between 1855 and 1863, Mendel uncovered the scientific explanation of biological inheritance through hybridization of the common garden pea (Pisum sativum).

Over nine years of hybridization studies of controlling the Anlagen or “foundations” for particular traits, and the use of more than 10,000 plants, Mendel outlined a theory based on elements, eventually to be known as “genes,” that were carried in the pea’s reproductive cells.

Johann Mendel, born July 22, 1822, was the only son of Rosine Schwirtlich, a gardener’s daughter, and Anton Mendel, an ex-Austrian army soldier who made a living as a peasant farmer.

He was raised in the town of Heizendorf in the northeastern section of Moravia. His parents were peasants scratching a living on a small farm. The town was a small German-speaking, God-fearing community. It was a very poor place, and even farmers who were fortunate enough to own small pieces of land, as Mendel’s father did, were subject to the robota.

The robota was a form of institutionalized forced labor (serfdom) that represented the last fragments of the ancient European feudal system. The 20th century word robot has its origins from the Czech author Karel Capek who described how peasants of the day lived.

Under the robota system, Mendel’s father was allowed to cultivate his own fruit trees and fields for four days each week; on the other three he was required to work for the local land owner. This was Mendel’s future: “a life spent on the farm and in the fields, a life of physical labor and drudgery, as much for the landlord as for himself, a life of brawn, not brain.”

The land holder that Anton Mendel owed robota was Maria Walburga, Grafin Truchsess von Waldburg-Zeil, who rewarded the people under her jurisdiction by providing a school for their children that was located at her chateau in the town of Kunin.

In 1802 Father Johann Schreiber was removed from his post as director of the school in Kunin and demoted and sent to a small village of Gross-Petersdorf as a parish priest, who was also to be responsible for Heinzendorf. It was in this small school where Johann Mendel and his sister Veronika, and his younger sister Theresia all began their education.

The famous naturalist, Christian Carl Andre, who would become a founding member of the Brunn Association for Sheep-Breeders, had been employed as an instructor at the institute that was the model for Father Schreiber’s school in Kunin. Andre supported the priest’s plan in the teaching of natural science, and Schreiber was a founding member of the Pomological (fruit-breeders) Association of Brno and member of the Brno Agricultural Society. Out of the Agricultural Society, a splinter society, The Society for Natural Science formed.

Thirty years later, it was to a meeting of The Society for Natural Science that the priest, Gregor Mendel, would read his famous paper on inheritance in the common garden pea.

Father Schreiber grew a small garden next to the school in Heinzendorf and used it to teach gardening and plant grafting. It was here that Johann Mendel learned of pollination and seed germination and the basic knowledge and skills of a plant-breeder.

Father Schreiber seemed to be everywhere in young Johann’s life: He baptized Mendel, he tutored Mendel, and on September 12, 1834, he filled out the entry and application from the baptismal register for the then fourteen-year-old Johann’s admission to the Gymnasium at Troppau .

Admission to the Gymnasium was a turning point in Johann Mendel’s life. As the only son of a peasant farmer he had now committed himself to six years of formal education at Troppau. He would live away from home and no longer be able to help on the family farm and would additionally be a drain on the family’s meager resources. He entered the Gymnasium on December 15, 1834.

Mendel’s parents saved the funds to send him to the Gymnasium in Troppau until he was sixteen, after which he financed himself by giving private lessons. At Troppau, Mendel lived on half-board (bed and a single meal each day) as that was what the collective family could afford. They also sent by carrier, on an irregular basis, home-grown vegetables to supplement his basic meals.

During the winter of 1838/39, Mendel’s father had a near-death logging accident that resulted in internal injuries and broken ribs, and at Pentacost of 1839 Johann temporarily left his schooling and returned to the farm.

In 1840, at the age of eighteen, Mendel entered into the Philosophy Institute at Olmutz that was a preparatory college of the university. In support of Mendel, his younger sister actually paid for his tuition with part of her dowry and proceeds from the sale of the family farm.

On July 14, 1843, Professor Friedrich Franz, a physicist, as well as a member of the holy orders, wrote to a friar:

Honored Colleague and very dear Friend!

As a result of your letter of June 12, I have made known to my pupils the Right Reverend Prelate’s decision to accept satisfactory candidates at your institution. Up to now, two candidates have given me their names, but I can only recommend one of them. This is Johann Mendel, born at Heinzendorf in Silesia.

On September 7, 1843, Mendel traveled to Brunn to be given a medical examination by a Dr. Schwarz in anticipation of his admission to the Augustinian Order. He was found to be perfectly healthy—on the 27th of September he was transferred from the diocese of Olmutz to that of Brunn, and on October 9, 1843, he was admitted to the convent of the Agustinians as a novice under the name of Gregor—he was now Gregor Mendel!

At the age of twenty one, Mendel entered into a religious order to pursue his scholarly ambitions. His fascination with science resulted in Mendel studying meteorology, bee culture and plant heredity along with teaching physics and natural history at Brunn’s Oberrealschule.

Mendel chose the garden pea as his research plant because it was self-fertilizing which favored the production of pure breeding varieties, “immune to accidental cross-pollination because of the keel-shaped anatomy of the pea flower, (thus) tightly enclosing the reproductive structures.”

Before Mendel started his pea hybridization studies he made sure that all of the traits he wanted to study were consistently expressed by growing thirty-four varieties side by side for two years, then to ensure that the crosses between varieties were correct he used the technique of artificial fertilization: the removal of the male organs from the flower to prevent self-pollination, then followed by the introduction of pollen from another variety. His goal had been “to obtain new variants” through further understanding of “the development of hybrids in their progeny.” It was through his statistical approach to variation that he demonstrated his originality as a scientist.

During the two years of study at the University of Vienna, Mendel learned that the reproduction of phanerogams (flowering plants) is produced by the union of one germinal cell (female) and one pollen cell (male) into a single cell. He rejected the prevailing theory that the pollen cell alone was the origin of the plant embryo. This belief was the very basis of his new analysis of variation.

At the recently opened Institute of Experimental Physics, where he attended lectures and courses on practical plant propagation, the director was the famous physicist Christian Doppler, the discoverer of the Doppler Effect. After only two years of study Doppler died and was replaced by Andreas von Ettingshausen. In 1826 Ettingshausen had published a textbook entitled Combinatorial Analysis. It is exactly this branch of mathematics, the study of combinations, patterns, and probabilities, that Mendel used to form his analysis of hybridization of the common garden pea.

In July of 1852 Mendel wrote to a fellow friar:

Dear Anselm,

It is a nuisance that I am once more short of under-linen. No one is in greater need of new under-linen than I am, for of the dozen shirts I brought with me to Vienna as many as 12 are frayed and in holes. Will you please ask Frau Smekal to spend 6 florins in buying linen for 5 shirts, and to get to work upon making them as soon as possible, so that I can at least have one new shirt for the exercises. Would it not be a scandal if the new man I shall become in consequence of the pious exercises were to go about in a frayed shirt? How ashamed I should be if I (Apocalypse: Stantes amict stolis albis—they stood clothed in white raiment) had to parade in torn vesture! The Herr Prelate has already notified me that I am to officiate at the exercises during the last week of hujus. Since, as you know, the lectures at the university finish on the 20th, and in this matter it would be stupid of me to try to piss in the wind’s eye, I have fixed the date of my return for Sunday the 24th, and shall arrive at Brunn toward noon.

Peter Matous (Klacel) is, I suppose still in the primeval forests of Trubau. Lucky devil! Leopoldstadt—next week. If tomorrow I win 25,000 fl. As the big prize in the lottery, I shall send a non-committal wire to Frau Smekal. Look her up without fail in the evening! To our speedy and happy (?) meeting!

Gregor

As an expert field botanist, Mendel understood how to recognize one species from another on the basis of contrasting traits. In evaluating the changes between generations of hybrids he followed the procedure of identifying hybrids in terms of defined pairs of contrasting characteristics (traits) of color, size, and shape of flowers and seeds to establish if they were related or variation occurred independently.

In 1854 Mendel procured thirty-four different varieties of pea seeds from local growers and then took two years of growing these peas to determine which varieties would have the correct characteristics and be suitable research subjects.

Mendel was seeking to find examples of “constant differentiating characters”— what is called “discontinuous variations” by 20th century geneticists.

Because of his training in combinatorial analysis under Ettingshausen, Mendel understood the mathematics of probability and outcome and as a result he chose to use quantitative observations rather than qualitative for documenting his research.

Mendel eliminated twelve varieties of peas from his research pool, leaving him with twenty-two from which he ultimately chose seven for his research:

1.             Smooth vs. wrinkled peas

2.             Yellow cotyledons with yellow peas vs. green cotyledons with green peas

3.             White seed coats with white flowers vs. grey seed coats with purple flowers

4.             Smooth vs. constricted pods

5.             Green vs. yellow pods

6.             Axial vs. terminal flowers

7.             Tall vs. dwarf plants

All twenty-two varieties were bred and reproduced during the entire duration of the experiment in order to demonstrate they all consistently bred true. Mendel chose the common garden pea (Pisum sativum) for his studies because it was self-pollinating, meaning pollen from the pea flower covers the stigma from the same flower before the flower bud opens, which guarantees that the peas that result have the same male and female “parent.”

The large immature pea flowers were easy to open, so Mendel was able to remove the nine anthers from each flower before they were mature in order to prevent self-pollination. After the anthers are extracted, the flower can be pollenated with pollen from another plant by means of a brush.

Mendel also used reciprocal crossing, which proved that both the male and female contributed equally to the resulting hybrid pea. Following the pollination process the flowers were covered with bags to prevent any chance of an unwanted contaminating pollination.

Mendel observed that 100 per cent of the seven pairs of contrasting pea characteristics that he studied segregated and recombined through successive generations. He demonstrated that for all traits the first generation hybrid were consistent in resembling one member of each contrasting pair of traits, i.e., all first generation plants from a cross between green and yellow-seeded varieties resulted in only yellow seeds, demonstrating that this was a dominant feature. He observed that dominance was identical no matter the direction of the cross, that is, yellow female, green male, and green male x yellow female.

All seven traits were sorting independently as they passed through the generations. With a physicist’s knowledge of probability and combination theory, he had seen through nine generations of crosses the transfer of traits both individually and in association with each other. Mendel had designed his research “to deduce a law” and by the time of publication, he had proved to himself that the law was as predictable as gravity.

Mendel came to understand that inheritance of characteristics was under the replicable control of elements (“genes”) from each of the parents through the sex cells into the offspring. He understood that there were two of these elements for each characteristic, one each produced by the male and female parent.

In 1866 Gregor Mendel recorded and published an accumulation of the results of his gardening experiments with peas. His classic landmark observations were published in the scientific journal Versuche Pflanzen Hybriden, where it languished for almost forty years. Mendel sent copies of his printed works to two highly-respected scientists. One copy remains missing and the second was found in an unopened envelope—his peers never grasped the magnitude of his observations and discovery.

Mendel’s observations went unnoticed until botanist Hugo de Vries, Erich von Tschermak, and Carl Correns rediscovered Mendel’s work. The three botanists re-ran Mendel’s experiments and their results were identical. All three (four if you include Mendel) “discovered” the laws of heredity.

Two years after Mendel had published his theory, the monastery’s abbot died and Mendel was elected to become the abbot. The added responsibilities diverted him from the pea garden, and the hybrid research came to a halt by 1871.

In 1878 Mendel was visited by a horticulturalist from France. As the two men walked through the gardens together Mendel showed the visitor labeled varieties of fruit trees, hot house plants, and well-groomed vegetable gardens. The vegetable gardens included “several beds of green peas in full bearing, which he said he had reshaped in height as well as in type of fruit to serve his establishment to better advantage.” When asked how he had created the new variety, Mendel responded, “It is just a little trick.”

De Vries found Mendel’s work referenced in a paper published in 1881. Through this study De Vries coined the term “mutation.” Focke, the author of the 1881 paper, summarized Mendel’s findings. However, it doesn’t appear that Focke had any idea of the magnitude or the scientific value of the information.

During the last decade of his life Mendel suffered from numerous degenerative diseases. He was obese, a heavy smoker, suffered from high blood pressure, dropsy, congestive heart failure, and progressive kidney failure.

But it appears that Mendel retained his famous humor until the end. In December of 1883, he wrote to one of his students who had become a meteorologist, “Since we are not likely to meet again in this world, let me take the opportunity of wishing you farewell, and invoking upon your head all the blessings of all the meteorological deities.” Mendel died early in the morning on January 6, 1884.

Mendel was buried three days after his death. A requiem mass was celebrated for him in the abbey church, the music conducted by the former pupil at the abbey choir school. After his burial in the section of the public cemetery reserved for the brothers of the Abbey of St. Thomas, his books were placed in the library of the convent and his official letters in the archive. His personal papers, his hand-written notes, and all of the records of his breeding experiments were taken out to the hill behind the convent and burned!

There was no news release, no public indication that perhaps one of the greatest scientists of all time had died.

Other Scientists Join the New Science 

Established by Darwin and Mendel

De Vries correctly interpreted Mendel’s research and referenced it in his own paper, which was published in 1900. Within months, Tschermak and Correns also discovered Mendel’s research through de Vries’ published works and indicated that their own independent research confirmed Mendel’s results.

When Mendel’s lost works were rediscovered, they were considered an alternative mechanism for the theory of evolution. De Vries was not satisfied with the Darwinian theory of gradualism to fully explain natural selection. He was searching for some support for his theory of evolution advancing in major leaps or “saltations.” His own theories of mutations appeared to provide additional support.

William Bateson was extremely influential in the world of science. When he read de Vries’ paper that referenced Mendel’s work, and being very astute, he knew that Mendel’s laws of inheritance were “revolutionary and absolutely correct.”

Bateson became excited and became Mendel’s voice in spreading word of the new science. He coined the terms genetics, allele (shortened from the original allelomorph), homozygote, and heterozygote. Bateson was additionally recognized for his discovery of linkage, which was confirmed by Morgan and Bridges.

It wasn’t until the 1920s and 1930s, after Morgan’s theories of chromosomal inheritance became universally understood and accepted, that researchers offered a blend of both Darwinism and Mendelian thought.

Biologist J. B. S. Haldane and Sewell Wright brought forth the theory that Mendelian genetics was the piece that Darwinian natural selection was missing— “the new combination theory could account for the production, generation after generation, of stable, inheritable variation on which natural selection could work.” Although Mendel had proposed this line of thinking in his classic paper, no one at the time had been educated enough to understand the material and take notice.

In 1902 an extremely original observation was made by a London physician, Archibald Garrod. His report in the British medical journal The Lancet, entitled, “The Incidence of Alkaptonuria: A Study in Chemical Individuality.”

Garrod saw many patients with the disease known as alkaptonuria, which was characterized by patients excreting large amounts of homogentisic acid in their urine. This substance turned black on contact with air so that the babies diapers would be stained black, alarming the mothers.

Alkaptonuria was not a disease that the patient caught from someone else, so was not a germ transmitted infectious disease, but rather was an “inborn error of metabolism”—a term that he came up with in 1908—meaning it was an unusual disease that was “inherited.”

Patients afflicted with alkaptonuria could not break down the amino acid tyrosine, which led to the abnormal accumulation of an intermediate metabolite, homogentisic acid. This non-lethal disease produced discoloration of the cartilage that was visible on the nose and ears, and produced arthritis, heart valve disease, and the black urine color.

Garrod postulated that this disease was an example of a rare recessive trait inherited in the classic Mendelian theory. He also suggested other many other recessive traits including albinism, a subject on which he published a book in 1909.

For the first time it was posited by Garrod that a gene biochemically allows an enzyme to function or not to function in certain steps of metabolism when he said: “. . . it will be seen that in the case of each of [the several known inborn errors of metabolism] the most probable cause is the congenital lack of some particular enzyme, in the absence of which a step is missed, and some normal metabolic change fails to be brought about.”

At the Rockefeller Institute in New York, the Russian-born Phoebus Levene, known for having collaborated with Kossel on nucleic acid at the early part of the 20th century, improved the analysis of nuclein, the gelatinous stuff in the nucleus.

Levene discovered the sugar deoxyribose and the linkage of these sugars together through phosphate groups. The molecule contained the four bases that Kossel had discovered: adenine, guanine, cytosine, and thymine. Bonded together —phosphate-sugar-base— these components formed a compound that Levene called nucleotide. He also discovered that the two forms of nucleic acid differed in their sugar component—ribose in one and deoxyribose in the second: therefore ribonucleic acid (RNA) and deoxyribonucleic acid (DNA).

By the 1930s, George Beadle and Edward Tatum were vigorously investigating the theory that enzyme deficiency produced a defect in a single metabolic step and they determined that Garrod’s theory was in fact a law: each step in a metabolic pathway was controlled by a specific enzyme molecule, and each enzyme came from a specific gene that could be changed (“mutated”) by exposure to X-rays—one gene: one enzyme. Enzymes were comprised of proteins, so the theory evolved into one gene: one protein.

Once again, it should be understood that Thomas Edison ended thousands of years of universal mineral supplementation that corrected mineral deficiencies of the average peasant when he pulled the switch at 3:00 pm in the afternoon on Monday, September 4th, 1882, on Pearl Street in New York City and opened up the first commercial electric generating plant and the first generating station that delivered 110 volts of direct current to 60 customers in lower Manhattan.

Edison lost the “War of the Currents” when alternating current became the most user-friendly distribution system of electricity. Even though he lost the distribution war, Edison’s power distribution system was significant for several reasons. First it established the potential commercial uses of such a system, and secondly it forever fostered the replacement of wood as the universal fuel. And, with the change to electrical power sources, it was the end of the historical source of the dietary mineral supplements of wood ashes.



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