While Miescher was isolating and discovering DNA in the 1860s, Austrian monk and botanist Johann Gregor Mendel (1822–1884) was experimenting with garden peas, demonstrating and documenting basic patterns of inheritance, now known as Mendel’s laws.
In 1856, Mendel began his decade-long research into inheritance patterns. He used the diploid garden pea, Pisum sativum, as his primary model system because it naturally self-fertilizes and is highly inbred, producing “truebreeding” pea plant lines—plants that always produce offspring that look like the parent. By experimenting with true-breeding pea plants, Mendel avoided the appearance of unexpected traits in offspring that might occur if he used plants that were not true-breeding. Mendel performed hybridizations, which involve mating two true-breeding individuals (P generation) that have different traits, and examined the characteristics of their offspring (first filial generation, F1) as well as the offspring of self-fertilization of the F1 generation (second filial generation, F2).
In 1865, Mendel presented the results of his experiments with nearly 30,000 pea plants to the local natural history society. He demonstrated that traits are transmitted faithfully from parents to offspring independently of other traits. In 1866, he published his work, “Experiments in Plant Hybridization,” in the Proceedings of the Natural History Society of Brünn. Mendel’s work went virtually unnoticed by the scientific community, which believed, incorrectly, in the theory of blending of traits in continuous variation.
He was not recognized for his extraordinary scientific contributions during his lifetime. In fact, it was not until 1900 that his work was rediscovered, reproduced, and revitalized by scientists on the brink of discovering the chromosomal basis of heredity.
Parker, N., Schneegurt, M., Thi Tu, A.-H., Forster, B. M., & Lister, P. (n.d.). Microbiology. Houston, Texas: OpenStax. Access for free at: https://openstax.org/details/books/microbiology