Gregor Johann Mendel
Founder of Modern Genetics
Mendel was born on July 22, 1822, in Heinzendorf, Austria (now Hyncice in the Czech Republic), a rural area where all schoolchildren received agricultural training. In 1842, he entered the Augustinian monastery in Brünn, Moravia (now Brno in the Czech Republic), where dedicated scholars and researchers sustained Mendel’s passion for science. After completing his theological education, Mendel entered the University of Vienna in 1851 to study the natural and physical sciences. There he learned to apply mathematics to experimental results and developed an interest in variation among plants, two factors that greatly influenced his subsequent work
In 1854, Mendel began to grow peas in the monastery garden to investigate how characteristics are inherited from parent to offspring. The pea plant was ideal for inheritance experiments because of its availability in distinguishable varieties, its short generation time, its production of many offspring, and its ability either to cross or self pollinate. Mendel carefully controlled the pollination of each plant so that he knew which parents gave rise to which offspring. From 1854 to 1863, he dedicated himself to the cultivation of more than 28,000 pea plants and to the analysis of the patterns of heredity for characteristics such as flower color and seed shape.
Many scientists at the time regarded heredity as a blending of the characteristics of the parents within the offspring, but this theory fell short of explaining many observable phenomena in plants and animals. An alternative idea suggested that parents pass on discrete heritable elements that retain separate intact identities within the offspring. Mendel’s experimental results illustrated the latter theory; today we call those hereditary elements genes. Mendel reported his conclusions to the local science society in 1865 and published them in Experiments with Plant Hybrids in 1866. He was elected abbot of his monastery in 1868. Mendel died in Brünn on January 6, 1884.
Gregor Johann Mendel’s Legacy
Mendel is considered to be the founder of genetics, a field that has illuminated and is crucial to the study of all biological disciplines.
The importance of Mendel’s remarkable achievements remained unrecognized until 16 years after his death. In 1900 three scientists, Hugo de Vries, Carl Correns, and Erich Tschermak von Seysenegg, independently rediscovered Mendel’s papers as they searched the existing literature for material to support the results of their own hybridization experiments. When they published their work, they cited Mendel as the first to have completed similar research.
Mendelian genetics underlie the modern understanding of how organisms inherit characteristics. Modern geneticists credit Mendel with having discovered the two basic laws of inheritance. In its modern version, Mendel’s law of segregation states that alleles (different forms of the same gene) are equally distributed among an organism’s gametes, or sex cells. This accounts for the even distribution of different alleles among offspring. Mendel’s law of independent assortment states that the alleles for one character are distributed among gametes independently of the alleles for other characters. This accounts for the abundance of variation in the characteristics of individual offspring from the same parents. Mendel’s laws apply to the basic genetics of all organisms.
Mendel’s work introduced the experimental and theoretical approach to heredity that is used in modern genetic analysis. Selective breeding programs, such as those employed by Mendel, increase the quality and productivity of the organisms from which humans obtain food, clothing, and pharmaceuticals. Mendelian analysis also enables genetic counselors to construct disease pedigrees of human families to determine the genetic makeup of potential parents and to predict the chance of a heritable disease appearing in their progeny.
Gregor Johann Mendel – 1822-1884