| 1865 |
|
Gregor Mendel, working alone
in an Austrian monastery, discovers that some characteristics
are inherited in ‘units’. |
| 1870 |
|
Friedrich Miescher isolates chemicals from
the cell nucleus, including ‘nucleic acids’.
However, most people are more interested in proteins in the
nucleus. |
| 1879 |
|
Walter Flemming describes behavior of chromosomes
during cell division, implicating these nuclear structures in
inheritance. |
| 1900 |
|
Hugo DeVries and others rediscover Mendel’s
work and establish first laws of inheritance. |
| 1909 |
|
Wilhelm Johannsen coins the term ‘gene’. |
| 1911 |
|
Thomas Hunt Morgan is the first to show
that genes are arranged in a linear fashion along
chromosomes. |
| 1928 |
|
Frederick Griffith uses a chemical extract
to convert harmless pneumonia bacteria into pathogenic forms.
The nature of this ‘inheritance factor’,
however, is unknown. |
| 1929 |
|
Phoebus Levene discovers that a sugar, deoxyribose,
is present in nucleic acids. Later identifies that DNA is made
up of nucleotides, a chemical unit comprising
a deoxyribose sugar, a phosphate group and
one of four small organic molecules known as bases. |
| 1941 |
|
George Beadle and Edward Tatum
show that genes direct the production of proteins.
|
| 1943 |
|
William Astbury makes the first X-ray
diffraction images of DNA.
|
| 1944 |
|
Building on Griffith’s work, Oswald Avery
and colleagues show that DNA can ‘transform’ cells,
cementing the link between DNA and genes.
|
| 1950 |
|
Edwin Chargaff discovers that there are
patterns in the amounts of the four bases in
DNA: the amounts of G and C, and of A and T, are always the
same.
|
| 1951 |
|
Rosalind Franklin takes her first X-ray
diffraction pictures.
|
| 1953 |
|
James Watson and Francis Crick
publish first paper proposing a double helix
structure for DNA.
Isaac Newton: “If I have seen further
it is by standing on the shoulders of giants.”
|
DNA
timeline