Basically, Mendel published the rules of heredity.
William James Beal develops the first clinically controlled crosses of corn in search of colossal yields.
The first rabies vaccine is developed.
The first cancer-causing virus is discovered by Rous.
Evans and Long discover the human growth hormone.
Alexander Fleming accidentally discovered penicillin.
Pauling showed that sickle cell anemia was a "molecular disease," a phrase which had not been used before. This was the result of a mutation in the protein molecule hemoglobin.
Kornberg discovers the enzyme DNA polymerase I, leading to an understanding of how DNA is replicated.
Xylose isomerase is discovered. It can convert glucose into fructose. Fructose is twice as sweet as glucose.
Congress funds the Human Genome Project, a massive effort to map and sequence the human genetic code as well as the genomes of other species.