Gregor Johann Mendel: A man far ahead of his times

The evidence-based model of inheritance in genetics that he presented was revolutionary.

Gregor Mendel. His work, together with Charles Darwin’s theory of evolution, laid the foundations of biology.  | Photo Credit: The Hindu Archives

In 1917, Thomas Hardy wrote the poem “Heredity”:

I am the family face;

Flesh perishes, I live on,

Projecting trait and trace

Through time to times anon,

And leaping from place to place

Over oblivion.

The years-heired feature that can

In curve and voice and eye

Despise the human span

Of durance—that is I;

The eternal thing in man,

That heeds no call to die.

A few years earlier, Gregor Johann Mendel’s scientific work was “rediscovered”. Mendel provided a clear explanation of how “flesh perishes” but “I live on”.

If Mendel had not been scared of seeing blood or if he had not failed an examination, we probably would not have got the concepts and principles of heredity from him. Mendel’s work, together with Charles Darwin’s theory of evolution, laid the foundations of biology.

200th birth anniversary

Mendel was born on July 20,1822, in Heinzendorf in Moravia within the Austrian Empire, now in the Czech Republic. The world is celebrating the 200th birth anniversary of this great scientist who was also a monk, not by choice but because, as he once wrote, “my circumstances decided my vocational choice”.

His father, Anton, owned a small fruit farm. The child Johann helped him. A falling log crippled Anton when Johann was quite young. Johann was often sick for long periods, so Anton was forced to work in spite of his crippled body. He would often say of Johann: “He is a disappointment for me.” Johann had a good relationship with his mother, Rosine, and his younger sister, Theresia.

When he was 11, he was sent to the Gymnasium in Troppau to finish his elementary and high school education. He was then enrolled in a programme at the Philosophical Institute in Olomouc for students who were high achievers in high school to prepare for university education. Being poor and often sick, he struggled with his studies. At the age of 19, he was bedridden for a year because of a neurological disorder, possibly depression. It was clear to the young Mendel that in spite of his early introduction to farming, he could never become a farmer as his father wanted him to be. And that even with financial support from his family, he simply could not afford a university education.

A life-changing suggestion

The Dutch botanist Hugo de Vries. In 1900,  after years of indifference, three botanists, de Vries, Carl Correns (Germany), and Erich von Tschermak (Austria), independently confirmed Mendel’s work. Actually, they had a dispute over who was the first to discover some important genetical ratios, and that brought Mendel’s paper into public awareness. | Photo Credit: Wikimedia Commons

At this critical juncture, Friedrich Franz, a priest and his physics teacher in the Gymnasium, who was impressed with Mendel’s talent in physics and natural science, made a life-changing suggestion. Franz informed Mendel that the Augustinian Order of the Catholic Church valued intellectual pursuits and suggested that priesthood could offer him a path to learning and teaching. Mendel grabbed the opportunity and joined St Thomas monastery in Brünn (now Brno) in 1843, where he changed his first name from Johann to Gregor. Cyril Napp (1792-1867), the abbot of St Thomas at the time, was also interested in science, particularly plant cultivation and animal breeding. He was helping farmers in the surrounding countryside grow better crops. Napp was the president of the agricultural society in Brünn. The monastery belonged to a liberal Catholic order guided by the credo “per scientiam ad sapientiam”, which means “from knowledge to wisdom over prayer”.

Napp found out that Mendel begun breeding mice to investigate coat-colour transmission and was aghast; he felt that it was “inappropriate for a priest to see sex”, so Mendel switched to breeding plants. Napp had a glasshouse (greenhouse) built for him so that he could pursue plant breeding. Napp had once told members of the Sheep Breeder’s Society that the questions to investigate were “what is inherited and how?” These questions motivated Mendel in his experiments later. Mendel demonstrated his sly sense of humour by once remarking: “You see, the bishop did not understand that plants also have sex.”

Mendel was ordained in 1847 after five years of study. He started to work in a parish hospital caring for the sick. He found it difficult and got sick himself from seeing the blood. Napp again came to Mendel’s rescue. He sent him to Vienna to study at the Royal Imperial University (1851-53). There, Mendel was taught courses on hybridisation by Franz Unger and on physics initially by Christian Doppler (who discovered the Doppler effect) and, after his death at the age of 49, by Andreas von Ettinghausen, who was an important influence in Mendel’s life. Mendel took classes in combinatorial mathematics, which helped him immensely when he had to analyse his plant observations.

Tug-of-war

Throughout his life, he was in a tug-of-war between science and orthodox religion. After he completed his coursework, Mendel took the teacher certification examination because he dreamt of being a professional teacher. During the oral examination, he argued with one of the examiners, Eduard Fenzl, who failed him.

An illustration  of the pea plant (Pisum sativum) species that Mendel used in his experiments.  | Photo Credit: Wikiwand

Back at St Thomas monastery, Mendel took comfort in his garden and started his breeding experiments with the pea plant (Pisum sativum). He also started to read about the first hybridisation experiments on tobacco by Josef Kolreuter and Carl Gaertner. But Mendel had doubts about their theory of “blending inheritance”, which stated that characteristics of offspring were midway between those of the two parents. Darwin also believed in “blending”.

Between 1856 and 1864, Mendel undertook a series of hybridisation experiments in the monastery’s garden, making tens of thousands of observations of plants to discover inheritance patterns. The experiments were breathtaking in the brilliance of their planning, observation, analysis, and interpretation of results and were designed to answer questions on offspring characteristics in relation to those of parents. His training with Unger in Vienna stood him in good stead. He was aware that in the mid 19th century counting, calculating ratios, and searching for laws on the basis of numerical data were rarely used in biological studies. Thus, Mendel was a unique member of the 19th-century intellectual community who derived laws in the biological sciences (“Mendel’s laws”) from counts and ratios.

Mendel pursued varied scientific activities. He was a co-founder and active member of the Brünn scientific society. He established a weather station at the monastery and wrote about weather forecasting. He studied sunspots. He analysed epidemiological data for correlations with changes in the water table. He tried his hand at beekeeping and became one of the very first people to breed bees systematically. He provided the first ever description of a tornado when he gave an account of one that swept through Brno in October 1870 and caused much damage.

Seminal paper

The German botanist Carl Correns. | Photo Credit: Wikimedia Commons

Mendel’s careful experiments and his meticulous quantitative observations and numerical calculations culminated in his seminal paper, “Experiments in Plant Hybridization”. With his breeder’s gaze, he analysed the pea plant not as a whole but as a collection of individual characteristics of interest. He did some pilot experiments to choose pairs of parental plants with contrasting characteristics, for example, having green or yellow as the pea colour, round or wrinkled as the pea shape, dwarf or tall as the plant height. Unlike breeders, his goal was not to improve these features or create new combinations of them but to ask general questions about their interactions and changing ratios. Will, for example, yellow and green blend to an intermediate colour or interact somehow to produce a wholly different colour? He wished to understand the extent to which parents contribute to characters of the offspring.

He presented his results to the Society for the Study of the Natural Sciences in Brünn in 1865. A scholar (Loren Eisley) wrote about it: “Stolidly the audience had listened. … No one had ventured a question, not a single heartbeat had quickened. … Not a solitary soul had understood him.” Mendel’s paper was published in the proceedings of the meeting in 1866, copies of which were sent to 133 associations of natural scientists and libraries in a number of countries. Mendel himself sent reprints to scholars and friends around Europe. However, there were only three citations of his work in the scientific literature in the next 35 years. Mendel was too far ahead of his time.

Towards the end of his career, he wrote: “I have experienced many a bitter hour in my life. Nevertheless, I admit gratefully that the beautiful, good hours far outnumbered the others. My scientific work brought me such satisfaction, and I am convinced the entire world will recognise the results of these studies.” To a friend he expressed his firm opinion: “Meine Zeit wird kommen [my time will come].”

Curbed academic freedom

The Austrian botanist Erich von Tschermak. | Photo Credit: Wikimedia Commons

Times were unfavourable in Austria. The monarchy fired hundreds of scholars and academics from teaching positions for political reasons. Scientific disciplines such as philosophy were barred from the university’s curriculum “in view of scandalous development of this science”, as noted by Patrick Alston in his book on education in tsarist Russia. Academic freedom in Austria was completely curbed. In response, Mendel drafted a petition, cosigned by a group of monks, “in the interest of mankind” requesting citizens to dedicate themselves to the pursuit of science freely and without prejudice.

After 35 years of neglect, in 1900, three botanists—Hugo de Vries (Holland), Carl Correns (Germany), and Erich von Tschermak (Austria)—independently confirmed Mendel’s work. Actually, they had a dispute over who was the first to discover some important genetical ratios such as 3:1 and 1:2:1, and it brought Mendel’s paper into public awareness. Mendel became a hero. His time had come.

Mendel provided an evidence-based model of inheritance, and we can speculate about why his contribution remained unappreciated and buried for 35 years. First, his discovery was “premature”. Those who make premature discoveries are liable to be ridiculed by their peers. Mendel was lucky that he was only ignored. Second, he was a monk and did not formally belong to the scientific establishment. Scientists do not normally accept discoveries by people outside their establishment. Third, the scientific method that Mendel used was revolutionary for his time. He may have been the first botanist who seriously applied mathematics to biology. Botanists worked by observation rather than by experimentation. The results of experiments by naturalists, such as Darwin, were judged by observation rather than by calculation. This is unquestionably why Mendel was so successful but is likely a reason why the world of natural science was not ready for his results. Fourth, he was shy and did not promote his discovery.

Trofim Lysenko

The Soviet agronomist Trofim Lysenko. He was instrumental in getting Stalin to ban Mendelian genetics in Russia  and in all countries under Russian influence.  | Photo Credit: Wikimedia Commons

The neglect of Mendel’s scientific contribution has many lessons for us. Our minds should be open to new ideas even if they are radical. Today, the words “novel” and “innovation” are widely used. Yet, if a Mendel were to reveal a “premature” discovery today, there is no guarantee that scientists would welcome the Mendel and his discovery. Scientists have certainly learnt to appreciate the importance of an interdisciplinary approach to science, but they are not yet free of bias nor yet open to ideas generated outside their establishment.

Unfortunately, the rational basis of Mendelism was completely undermined during the rule of Joseph Stalin (1878-1953). In the 1940s, the Soviet agronomist Trofim Lysenko (1898-1976), director of the USSR’s institute of genetics, persuaded Stalin that environmentally modified characteristics were heritable via all cells of the organism. This offered proof of the Marxist concept of societal evolution. Stalin banned Mendelian genetics in Russia and in all countries under Russian influence.

Lysenko’s treatment of Mendelian principles also has lessons for us. His attack on Mendelian science and his propounding a theory (inheritance of environmentally acquired characters) that was not based on any scientifically derived evidence but on what was ideologically attractive to the totalitarian regime resulted in the persecution, and even death, of many scientists who opposed him or supported Mendelian theory.

Postscript

Mendel’s laws are universal. The Mendelian universe transcends pea plants and the colour and shape of peas. It is remarkable how quickly scientists discovered that Mendel’s results held not only for pea plants but also for humans. The British physician Archibald Garrod announced in 1902, two years after the rediscovery of Mendel’s laws, that the transmission of a human disease called alkaptonuria—with symptoms that include discolouration of skin and dark urine—conformed to Mendelian laws. Mendel was the first person to shed light on one of the greatest phenomena of nature.

In the last decade of his life, he got embroiled in a hopeless conflict. The Austrian government levied an exorbitant tax on the monastery, where he was now the abbot. He refused to pay right up to his death on January 6, 1884, from congestive heart and kidney failure. A few years afterwards, the Austrian government withdrew its policy of taxation of monasteries.

Partha P. Majumder is National Science Chair (Scientific Excellence), Government of India; distinguished professor and founder, National Institute of Biomedical Genomics, Kalyani, West Bengal; emeritus professor, Indian Statistical Institute, Kolkata; honorary professor, Indian Institute of Science Education & Research, Mohali and Kolkata.

The Crux

• This year is the 200th anniversary of Gregor Mendel, who is considered the father of genetics.
• Between 1856 and 1864, Mendel undertook a series of hybridisation experiments on the pea plant, making tens of thousands of observations to find out how certain characteristics were passed on from parents to offspring.
• In 1865, he presented his seminal paper, “Experiments in Plant Hybridization”, to the Society for the Study of the Natural Sciences in Brünn.
• The significance of his work was not understood. Mendel was too far ahead of his time.
• in 1900, three botanists—Hugo de Vries (Holland), Carl Correns (Germany), and Erich von Tschermak (Austria)—independently confirmed Mendel’s work. Mendel became a hero.
• But not in his lifetime: He died on January 6, 1884, from congestive heart and kidney failure.