isolated the first crude preparation of DNA and named it nuclein.
Gregor Mendel discovered the fundamental laws of inheritance through the work/experiment on pea plants
Hugo de Vries furthered on the peas plant experiment and came up with similar conclusion. However, he included a theory on mutation.
Proposed the idea of a triple-stranded helix structure for DNA.
Thomas Hunt Morgan established the chromosomal theory of inheritance. He and his friends developed the ideas, and provided the proof for the chromosomal theory of heredity, genetic linkage, chromosomal crossing over and non-disjunction.
produced the X-ray crystallography pictures of BDNA which Watson and Crick used to determine the structure of double-stranded DNA.
Hermann Muller showed that X-Rays could induce mutations. Although he won Nobel prize for that, it angered many doctors because it raised precaution to many on X-Ray usage.
With Francis Crick, they proposed the idea that DNA was a double helix structure, which was soon recognized as true.
Provirus theory, which was said that RSV and other RNA viruses entered the cell and then made DNA copies of themselves before integrating into the host genome.
Erwin Chargaff discovered the pattern on the nitrogenous base in DNA, where Adenine(A) pairs up with Thymine(T) and Guanine(G) pairs up with Cytosine(C).