An editorial in Nature Genetics in January, A very Mendelian year, reminded us of the 200th birth anniversary of Gregor Mendel, the ‘father of modern genetics’, on July 20, 2022. The legacy of Mendel is intriguing. Mendel performed controlled crossing experiments on around 29,000 plants with the garden pea between 1856 and 1863. He registered many observable characteristics, such as the shape and colour of the seeds, the colour of the flower, and formulated two principles of heredity. His seminal paper, ‘Experiments on Plant Hybridization’, was published in the Proceedings of the Brunn Society for Natural Science in 1866. He, however, gained posthumous recognition when, in 1900, the British biologist William Bateson unearthed Mendel’s paper.
The issue of falsification
Importantly, in 1936, eminent British statistician and geneticist, Sir Ronald Fisher, published a paper titled Has Mendel’s Work Been Rediscovered? By reconstructing Mendel’s experiments, Fisher found the ratio of dominant to recessive phenotypes to be implausibly close to the expected ratio of 3:1. He claimed that Mendel’s data agree better with his theory than expected under natural fluctuations. “The data of most, if not all, of the experiments have been falsified so as to agree closely with Mendel’s expectations,” he concluded. Fisher’s criticism drew wide attention beginning in 1964, about the time of the centenary of Mendel’s paper. Numerous articles have been published on the Mendel-Fisher controversy subsequently. The 2008 book, Ending the Mendel-Fisher Controversy, by Allan Franklin and others recognised that “the issue of the ‘too good to be true’ aspect of Mendel’s data found by Fisher still stands.” Fisher, of course, attributed the falsification to an unknown assistant of Mendel. Modern researchers also tend to give the benefit of the doubt to Mendel.
