| Year |
Scientist(s) |
Discovery |
| 1858 |
Charles Darwin Alfred Russel Wallace |
Joint announcement of the theory of natural
selection-that members of a population who
are better adapted to the environment survive
and pass on their traits. |
| 1859 |
Charles Darwin |
Published The Origin of Species. |
| 1866 |
Gregor Mendel |
Published the results of his investigations
of the inheritance of "factors" in pea plants. |
| 1900 |
Carl Correns Hugo de Vries Erich von Tschermak |
Mendel's principles were independently discovered
and verified, marking the beginning of modern
genetics. |
| 1902 |
Walter Sutton |
Pointed out the interrelationships between
cytology and Mendelism, closing the gap between
cell morphology and heredity. |
| 1905 |
Nettie Stevens Edmund Wilson |
Independently described the behavior of
sex chromosomes-XX determines female; XY determines
male. |
| 1908 |
Archibald Garrod |
Proposed that some human diseases are due
to "inborn errors of metabolism" that result
from the lack of a specific enzyme. |
| 1910 |
Thomas Hunt Morgan |
Proposed a theory of sex-linked inheritance
for the first mutation discovered in the fruit
fly, Drosophila, white eye. This was followed
by the gene theory, including the principle
of linkage. |
| 1927 |
Hermann J. Muller |
Used x-rays to cause artificial gene mutations
in Drosophila. |
| 1928 |
Fred Griffith |
Proposed that some unknown "principle" had
transformed the harmless R strain of Diplococcus
to the virulent S strain. |
| 1931 |
Harriet B. Creighton
Barbara McClintock |
Demonstrated the cytological proof for crossing-over
in maize. |
| 1941 |
George Beadle
Edward Tatum |
Irradiated the red bread mold, Neurospora,
and proved that the gene produces its effect
by regulating particular enzymes. |
| 1944 |
Oswald Avery
Colin MacLeod
Maclyn McCarty |
Reported that they had purified the transforming
principle in Griffith's experiment and that
it was DNA. |
| 1945 |
Max Delbruck |
Organized a phage course at Cold Spring
Harbor Laboratory which was taught for 26
consecutive years. This course was the training
ground of the first two generations of molecular
biologists |
| late 1940s |
Barbara McClintock |
Developed the hypothesis of transposable
elements to explain color variations in corn. |
| 1950 |
Erwin Chargaff |
Discovered a one-to-one ratio of adenine
to thymine and guanine to cytosine in DNA
samples from a variety of organisms. |
| 1951 |
Rosalind Franklin |
Obtained sharp X-ray diffraction photographs
of DNA. |
| 1952 |
Martha Chase
Alfred Hershey |
Used phages in which the protein was labeled
with 35S and the DNA with 32P for the final
proof that DNA is the molecule of heredity. |
| 1953 |
Francis Crick
James Watson |
Solved the three-dimensional structure of
the DNA molecule. |
| 1958 |
Matthew Meselson
Frank Stahl |
Used isotopes of nitrogen to prove the semiconservative
replication of DNA. |
| 1958 |
Arthur Kornberg |
Purified DNA polymerase I from E. coli,
the first enzyme that made DNA in a test tube. |
| 1966 |
Marshall Nirenberg
H. Gobind Khorana |
Led teams that cracked the genetic code-
that triplet mRNA codons specify each of the
twenty amino acids. |
| 1970 |
Hamilton Smith
Kent Wilcox |
Isolated the first restriction enzyme, HindII,
that could cut DNA molecules within specific
recognition sites. |
| 1972 |
Paul Berg
Herb Boyer |
Produced the first recombinant DNA molecules. |
| 1973 |
Joseph Sambrook |
Led the team at Cold Spring Harbor Laboratory
that refined DNA electrophoresis by using
agarose gel and staining with ethidium bromide. |
| 1973 |
Annie Chang
Stanley Cohen |
Showed that a recombinant DNA molecule can
be maintained and replicated in E. coli. |
| 1975 |
|
International meeting at Asilomar, California
urged the adoption of guidelines regulating
recombinant DNA experimentation. |
| 1977 |
Fred Sanger |
Developed the chain termination (dideoxy)
method for sequencing DNA. |
| 1977 |
|
The first genetic engineering company (Genentech)
is founded, using recombinant DNA methods
to make medically important drugs. |
| 1978 |
|
Somatostatin became the first human hormone
produced using recombinant DNA technology. |
| 1981 |
|
Three independent research teams announced
the discovery of human oncogenes (cancer genes). |
| 1983 |
James Gusella |
Used blood samples collected by Nancy Wexler
and her co-workers to demonstrate that the
Huntington's disease gene is on chromosome
4. |
| 1985 |
Kary B. Mullis |
Published a paper describing the polymerase
chain reaction (PCR), the most sensitive assay
for DNA yet devised. |
| 1988 |
|
The Human Genome Project began with the
goal of determining the entire sequence of
DNA composing human chromosomes. |
| 1989 |
Alec Jeffreys |
Coined the term DNA fingerprinting and was
the first to use DNA polymorphisms in paternity,
immigration, and murder cases. |
| 1989 |
Francis Collins
Lap-Chee Tsui |
Identified the gene coding for the cystic
fibrosis transmembrane conductance regulator
protein (CFTR) on chromosome 7 that, when
mutant, causes cystic fibrosis. |
| 1990 |
|
First gene replacement therapy-T cells of
a four-year old girl were exposed outside
of her body to retroviruses containing an
RNA copy of a normal ADA gene. This allowed
her immune system to begin functioning. |
| 1993 |
|
FlavrSavr tomatoes, genetically engineered
for longer shelf life, were marketed. |
