200 Years of Mendel

Gregor Mendel (1822-1884)

Gregor Johann Mendel was an Augustinian prelate working in the fields of botany, meteorology, mathematics, and teaching. From 1840-1843 Mendel studied at the Palacky University Olomouc, excelling in physics and mathematics. He subsequently studied physics, from 1851-1853, at the University of Vienna under Christian Doppler, taking further courses in chemistry and zoology.

In 1854 Mendel received a permit for a major experimental program in plant hybridization; he was to monitor and pattern the hereditary characteristics that were inherited by successive generations of the edible pea, scientifically known as Pisum sativum. To track inherited characteristics, Mendel chose 7 distinctive phenotypes (the form of ripe seed: smooth or wrinkled, colour of flower: purple or white, length of stem: tall or dwarf, etc.). He crossed these character-pairs with one another, and called the offspring ‘hybrids’. The first generation of these hybrids displayed one of the two character traits and considered this trait ‘dominant’. The second generation, however, showed both dominant and recessive traits in the ratio of approximately 3:1, respectively. Upon studying successive generations, Mendel found that 2 thirds of the dominant phenotype peas were heterozygous, and the remaining third were homozygous. Therefore, the ratio 3:1 is essentially 1:2:1, suggesting 50% of this generation was true-breeding, and the remaining 50% were hybrids.

Through this research, Mendel discovered the fundamental laws of heredity and the mathematical basis of genetic science.

A link to his original study:

http://www.esp.org/foundations/genetics/classical/gm-65.pdf