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| Year : 2010 | Volume : 1 | Issue : 1 | Page : 3-4 |
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Gregor Johann Mendel: The father of modern genetics
Adi E Dastur1, PD Tank2
1 Dean and Honorary Consultant, Nowrosjee Wadia Maternity Hospital, Mumbai, India
2 Honorary Clinical Associate, Nowrosjee Wadia Maternity Hospital, Mumbai, India
| Date of Web Publication |
31-Mar-2010 |
Correspondence Address:
Adi E Dastur
103, Razak Haven, 12 Darabsha Lane, Napean Sea Road, Mumbai 400 026
India
DOI: 10.4103/0976-1756.62132
How to cite this article:
Dastur AE, Tank P D. Gregor Johann Mendel: The father of modern genetics. J Prenat Diagn Ther 2010;1:3-4 |
How to cite this URL:
Dastur AE, Tank P D. Gregor Johann Mendel: The father of modern genetics. J Prenat Diagn Ther [serial online] 2010 [cited 2013 Oct 6];1:3-4. Available from: https://jpdt.org/text.asp?2010/1/1/3/62132 |
The passage of characteristics from parent to child is a phenomenon that has been cloaked in mystery since time immemorial. The fact that there is a transmission of characteristics through generations was recognized even in Neolithic times. Hippocrates (400 BC) proposed that that tiny particles from every part of the body of each parent became blended, producing an individual with the characteristics of both. Up until the 17 th century, the scientific thinking about reproduction was dominated by "preformation": the idea that an organism contains all of its future descendants, encased in increasingly miniature forms, like Russian nesting dolls. It was in the late 1700s that farmers and sheep breeders, especially in Britain pioneered the study of hybrids only as a means to improve yields from plants and animals. It was therefore appropriate that the mysteries of heredity were unraveled by someone whose origins lay on the farm.
Johann Mendel was born into a German farming family in Heinzendorf bei Odrau, Austrian Silesia, Austrian Empire (now Hynèice, Czech Republic), and was baptized two days later. He was the son of Anton and Rosine Mendel. They lived and worked on a farm which had been in the Mendel family for at least 130 years. During his childhood, Mendel worked as a gardener, studied beekeeping and developed a broad interest in the natural sciences. Upon recommendation of his physics teacher Friedrich Franz, he entered the Augustinian Abbey of St Thomas in Brno in 1843. He took the name Gregor upon entering monastic life. The Augustinians were known as teachers, and Mendel was sent to study for his teacher's certificate. He took the examination in 1850 but the examiner commented that he lacked "insight, and the prerequisite clarity of knowledge." Mendel never did succeed in gaining a teacher's diploma, though he was sent to the University of Vienna in 1851. At Vienna, his professor of physics was Christian Doppler. Mendel returned to his abbey in 1853 chiefly as a physics tutor. Mendel worked on various aspects of physics and had a number of papers on meteorology to his credit. The latter part of his life after the pea experiment was spent in administrative work after he was elected Abbot of his monastery in 1869. [1]
It was Mendel's native curiosity and early experiments with hybridizing ornamental plants that gave birth to the idea of heredity. Mendel quietly began a methodical investigation in to the nature of heredity using pea plants (Pisum sativum). The experiment spread from the kitchen garden to over two acres of the monastery gardens and took eight years (1858-1866) to conduct. He personally pollinated the flowers of about 28000 plants. Earlier scientists had noticed the disappearance and reappearance of traits in hybrid plants. What Mendel did differently was count assiduously. Mendel used mathematics to draw conclusions about what was happening deep inside the cell and this helped him to see the hidden patterns of heredity.
Mendel's famous pea experiment began by identifying seven pairs of contrasting traits found among garden peas: seed color (yellow or green), seed shape (smooth or wrinkled), pod color (yellow or green), pod shape (inflated or pinched), flower color (purple or white), flower position (axial or terminal) and stem height (tall or short). For two years, he grew different varieties of peas to make sure that their offspring were always the same. Then be began breeding different varieties together to make hybrids. He then grew generation after generation of hybrids and tracked the inheritance of the traits. Mendel noticed that some traits disappeared in the first generation of hybrids. He called these traits "recessive." He called those that did appear "dominant." In later generations the recessive traits reappeared-and in a mathematically predictable pattern. For example, later generations of plants had one green pea for every three yellow peas. The same ratio appeared for all seven pairs of traits. These studies helped Mendel to crystallize the first of the Laws of Inheritance. The Law of Segregation states that hereditary factors do not combine, but are passed intact. In later studies, Mendel went on to cross plants that differed in more than one trait-round-yellow peas with wrinkled-green ones, or tall, violet-blossomed plants with short, white-blossomed ones. As in his initial experiments, the traits appeared in predictable ratios. This told Mendel that the elements governing traits were not linked, but passed separately to the offspring - The Law of Independent Assortment.
Mendel read his paper, Experiments on Plant Hybridization, at two meetings of the Natural History Society of Brünn in Moravia in 1865. When Mendel's paper was published in 1866, it had little impact and was cited about three times over the next thirty-five years. [ 2] Notably, Charles Darwin was unaware of Mendel's paper. He may have been disheartened by the lack of reaction to his pea paper, but he knew that his discovery was important. Not long before his death in 1884 he told a scientific colleague, "My time will come." Mendel was right. In 1900 three European botanists rediscovered his work and set off a scientific explosion. [3] The units of hereditary characteristics were christened "genes" in 1909 by the Danish biologist Wilhelm Johannsen. His work was criticized later for being an example of confirmation bias. But further experiments by independent scientists reproduced the results in plant and animal hereditary characteristics. It is a mark of his posthumous status that the term "Mendelian genetics" is virtually synonymous with the study of heredity.[Figure 1]
 References |
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| 1. |
Orel V. Gregor Mendel the first geneticist. Oxford: Oxford University Press; 1996.  |
| 2. |
Mendel JG. Versuche über Plflanzenhybriden Verhandlungen des naturforschenden Vereines in Brünn, Bd. IV für das Jahr, 1865 Abhandlungen1866:3-47. For the English translation, see: Druery CT, Bateson W. Experiments in plant hybridization. Journal of the Royal Horticultural Society 1901;26:1-32. |
| 3. |
Masaryk University Mendel Museum. The Mendel Exhibition online. Mendel: Man and Mind. [document on the Internet]. Available from: http://www.mendel-museum.com/eng/1online/room1.htm. [cited in 2002]. |
[Figure 1]
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