Gregor Johann Mendel

On August 6, 1847, Gregor Johann Mendel was ordained as a priest in Brünn, Moravia. Luckily for medicine, Mendel's personality and psychosomatic disposition rendered him unsuitable for practical pastoral duties. It was 18 years later that the results of his famous experiments with the garden pea were presented to the Brünn Natural History Society. In the following year, the landmark work, “Experiments on Plant Hybrids,” was published. Even the enigmatic Mendel, who elucidated the fundamental principles of genetics, was perhaps unaware of the monumental nature of his work. Upon his death in 1884, no one had yet recognized him as the founder of a new and powerful science; the belated discovery of this cloistered monk would come years later.Born Johann Mendel in July 1822, in Heizendorf, Silesia (then in Austria), Mendel hailed from a humble family of peasants devoted to farming and gardening. Johann Schreiber, a priest from a Moravian parish, recognized the immense talent in the young Mendel and encouraged the family, which was under dire financial circumstances, to send Mendel for higher education. Schreiber was an expert fruit grower with a special interest in natural history and would have a lasting influence on Mendel. It was with all of Mendel's strength and endurance and the support of his family that he was able to complete his 2-year course of philosophical studies.When Mendel's father died, the financial hardship facing his family became more severe. Mendel tried private tutoring, but with his perpetual struggle to make ends meet, he could see no satisfactory worldly existence compatible with his intellectual ideals. He thus turned to theology as a vocational choice, and joined the Augustinian Monastery in Brno (Brünn) in 1843.At the time, Brünn was a thriving cultural center in Moravia. The abbot of this monastery, Franz Cyrill Napp, was an enigmatic figure. An ardent linguist proficient in ancient Oriental languages, Napp had many other passions, including horticulture, viniculture, and fruit growing. Many exotic plants were grown in Napp's monastery. It was in this monastery that the young Mendel stepped in, taking the name Gregor.There was intense interest in animal and plant breeding in Moravia, and Napp was intrigued by the principles of breeding and heredity. Napp was intimately involved with the Moravian-Silesian Agricultural Society. The astonishing results of some area sheep breeders on combining and improving valuable traits were discussed in detail at the meetings of the society. The question of plant improvement was particularly significant for fruit growers. No doubt, Mendel's interest in heredity was aroused by these discussions.For 4 years, Mendel pursued his theological studies, and he was ordained as a priest in August 1847. But it soon became apparent that Mendel was unfit for pastoral duties, as the very sight of suffering made him ill. The intuitive Napp realized this and excused Mendel from pastoral duties and assigned him to teaching. In the abbey, Mendel's life was enriched not only by Napp, but also by several other intellectuals, scientists, and botanists.Mendel twice failed to pass the official examination required for natural science teachers. He thus lacked the state qualifications to teach and settled into a career of teaching in a local school. Napp, who saw tremendous potential in Mendel, arranged for Mendel's university studies in Vienna, with the expenses covered by the monastery. Napp himself had originated from a poor family and supported young men from similar social circumstances.From 1856 to 1863, Mendel conducted his famous plant breeding experiments with the garden pea (Pisum sativum). These experiments took place in a narrow garden in the abbey, which measured 35 m long and 7 m wide. Mendel essentially found the same pattern for all 7 traits he studied, and he derived the mathematical formula that defined the laws of heredity. Mendel's work remains a classic, outlining the results of experimental work with painstaking observations on 7 pairs of contrasting characters. These characters included those affecting the seed (wrinkled or round, yellow or green, and gray or white seedcoat) and those affecting the plant (distribution of flowers, shape and color of pods, and length of stem). Mendel's laws of segregation and the law of independent assortment of characters are now recognized as the fundamental principles of heredity. He noted that each trait was inherited as a separate unit; these units of heredity would later be named genes. Mendel introduced the terms dominant and recessive.Mendel elucidated the basic patterns of inheritance by performing carefully planned experiments on the common garden pea, an extremely wise choice of experimental model. Pea plants proved to be excellent subjects for simple genetic experiments, as they had some easily recognizable, clear-cut differences in external characteristics.When Mendel read his paper entitled “Experiments on Plant Hybrids” in 1865 before the Brünn Natural History Society, little discussion followed. This work was published in the proceedings of the society in the following year (1866), but would remain in obscurity for more than 30 years.For years, Mendel maintained a scientific correspondence with Carl Naegeli, a leading German scientist. Naegeli steered Mendel in the direction of the hawkweed, which proved to be a complicated and unfortunate experimental model.Two years after publication of his paper on the garden pea, Mendel was elected abbot of the monastery. His life thereafter became involved in administrative problems. In particular, Mendel was saddened by a dispute concerning the taxation of the monastery property.The founder of genetics, Mendel died January 6, 1884, after a long bout with chronic nephritis. In his final years, the conflict with government officials on religious taxes took a toll on his health. Yet, Mendel was an enigmatic figure whose life was marked not only by remarkable successes, but also by many adversities and disappointments. A combination of factors, including dire financial situations, inadequate nutrition, and illness, forced him into a vocational choice borne out of the necessity to survive. Failure to pass the board examinations for teaching certification was a blow to him, but had Mendel been successful, he would have had little opportunity to devote long hours to his experiments with the garden pea.Mendel was indeed before his time—the monumental significance of his work was not recognized by his peers. At the dawn of the 20th century, 3 researchers, Hugo DeVries, Karl Correns, and Erich von Seysenegy Tschermak, independently discovered the mendelian principles. Unappreciated in life, one posthumous honor after another has been bestowed on this extraordinary monk.

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