There is not a single person who is a pioneer for modern genetic theory, because many scientists have contributed to our present knowledgs of genetics. For example, Gregor Mendel did many experiments with peas, that lead him to develop 2 important laws that are still used today. The law of independent assortment and the Law of Segregation. Many other scientists made many other discoveries that paved the way for modern genetics, such as Watson and Crick, who discovered the structure of DNA, Frederick Meischer, the man who discovered DNA.
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