-
Erwin Chargaff shows there are equal amounts of the nucleotides adenine and thymine (known as A and T) as well as equal amounts of guanine and cytosine (known as G and C) in every DNA strand,
-
Martha Chase and Alfred Hershey demonstrate that not viral protein and viral DNA direct the reproduction of new viruses, thus confirming that DNA is the molecule that mediates heredity.
-
Maurice Wilkins and Rosalind Franklin take X-ray's of DNA crystals which later leads Watson and Crick toward their famous conclusions.
-
James Watson and Francis Crick describe the 3D structure of DNA as a double helix: two spiraling strands held together by complimentary base pairs (such as Adenine and Thymine or Cytosine and Guanine).
-
A total of three copies of chromosome 21 causes Down's syndrome as determined by Jerome Lejeune.
-
Francis Crick, H. Gobind Khorana, Marshall Nirenberg, George Gamow, and other scientists crack the genetic code -- 64 nucleotide triplets that make up a universal genetic code for all cells and viruses.
-
Werner Arber isolates restriction enzymes in DNA.
-
Building upon the work of a Stanford graduate student and his faculty advisor, Paul Berg uses restriction enzymes to splice DNA, thus creating the first strand of recombinant DNA.
-
Fred Sanger and other scientists sequence a strand of DNA.
-
The first complete DNA genome to be sequenced is bacteriophage φX174
-
Kary Mullis developes the Polymerase Chain Reaction, used to date the most accurate and sensitive methods for amplifying DNA.
-
Applied Biosystems markets the first automated sequencing machine, the model ABI 370.
-
Craig Venter, Hamilton Smith, and colleagues at The Institute for Genomic Research (TIGR) publish the first complete genome of a living organism, Haemophilus influenzae, a bacterium. Its publication in the Journal Science marks the first use of whole-genome shotgun sequencing, consequently eliminating the necessity of the initial mapping efforts.
-
A draft sequence of the human genome is published.
