
DNA an Genetics History Timeline
By: Michael Kalu
1 January 1866
Gregor Mendel
Gregor Mendel published work on hereditary traits in peas. He notes that certain traits are passed from parent to offspring. Later these factors were called genes.

1 January 1869
Friedrich Miescher
Friedrich Miescher discovers an acidic substance in a cell's nuclei. This substance, first called nuclein, is now identified as DNA.

1 January 1882
Walther Flemming
Walther Flemming discovers a substance he calls chromatin. He notices that, during cell division, this substance separates into threadlike strings, which become known as chromosomes.

1 January 1902
Boveri and Sutton
Mendel’s research is rediscovered by botanists Theodor Boveri and Walter Sutton in 1900. Then they independently notice the link between Mendel’s “units of inheritance” and chromosomes. They conclude that hereditary information is contained within chromosomes.
1 January 1910
Thomas Hunt Morgan
Thomas Hunt Morgan is the first to discover a sex-linked trait while studying the fruit fly Drosophila. The trait for eye color, on the X chromosome, is also the first gene to be traced to a specific chromosome.

1 January 1944
Avery, MacLeod and McCarty
Oswald Avery, Colin MacLeod, and Maclyn McCarty revisit work from the 1920s and prove that, in bacteria, DNA is the hereditary material and not protein as was previously suspected in 1951.

1 January 1950
Erwin Chargaff
in 1950, Erwin Chargaff discovers regularity in proportions of DNA bases for different species. In all organisms he studies, the amount of adenine (A) approximately equals that of thymine (T), and guanine (G) equals cytosine (C).

1 January 1953
Crick and Watson
James Watson and Francis Crick, with contributions from Rosalind Franklin and Maurice Wilkins, discover the double helix structure of DNA.

1 January 1990
The Human Genome Project
The international Human Genome Project begins, with the goal of sequencing the entire human genetic code. Gene therapy is used successfully for the first time, to treat a four-year-old girl with the rare hereditary immune disorder adenosine deaminase deficiency.

1 January 2003
The Human Genome Project Completed
Human Genome Project is completed and confirms humans have approximately 20,000–25,000 genes. The human genome is sequenced to 99.99 percent accuracy, 2 years ahead of schedule.
