Watson and Crick discover chemical structure of DNA
On February 28, 1953, Cambridge University scientists James D. Watson and Francis H.C. Crick announce that they have determined the double-helix structure of DNA, the molecule containing human genes.
Though DNA—short for deoxyribonucleic acid—was discovered in 1869, its crucial role in determining genetic inheritance wasn’t demonstrated until 1943. In the early 1950s, Watson and Crick were only two of many scientists working on figuring out the structure of DNA. California chemist Linus Pauling suggested an incorrect model at the beginning of 1953, prompting Watson and Crick to try and beat Pauling at his own game.
On the morning of February 28, they determined that the structure of DNA was a double-helix polymer, or a spiral of two DNA strands, each containing a long chain of monomer nucleotides, wound around each other. According to their findings, DNA replicated itself by separating into individual strands, each of which became the template for a new double helix. In his best-selling book, The Double Helix (1968), Watson later claimed that Crick announced the discovery by walking into the nearby Eagle Pub and blurting out that “we had found the secret of life.” The truth wasn’t that far off, as Watson and Crick had solved a fundamental mystery of science–how it was possible for genetic instructions to be held inside organisms and passed from generation to generation.
Watson and Crick’s solution was formally announced on April 25, 1953, following its publication in that month’s issue of Nature magazine. The article revolutionized the study of biology and medicine. Among the developments that followed directly from it were pre-natal screening for disease genes; genetically engineered foods; the ability to identify human remains; the rational design of treatments for diseases such as AIDS; and the accurate testing of physical evidence in order to convict or exonerate criminals.
Crick and Watson later had a falling-out over Watson’s book, which Crick felt misrepresented their collaboration and betrayed their friendship. A larger controversy arose over the use Watson and Crick made of research done by another DNA researcher, Rosalind Franklin, whose colleague Maurice Wilkins showed her X-ray photographic work to Watson just before he and Crick made their famous discovery. When Crick and Watson won the Nobel Prize in 1962, they shared it with Wilkins. Franklin, who died in 1958 of ovarian cancer and was thus ineligible for the award, never learned of the role her photos played in the historic scientific breakthrough.
RELIGION
2013
Pope Benedict resigns
On February 28, 2013, less than three weeks after making the unexpected announcement that he would step down, 85-year-old Pope Benedict XVI officially resigns. Citing advanced age as the reason for giving up his post as the leader of the 1.2 billion-member Roman Catholic Church.
1990S
1994
First NATO Military Action
In the first military action in the 45-year history of the North Atlantic Treaty Organization (NATO), U.S. fighter planes shoot down four Serbian warplanes engaged in a bombing mission in violation of Bosnia’s no-fly zone. The United States, 10 European countries, and Canada.
ART, LITERATURE, AND FILM HISTORY
1982
Getty Museum endowed
On February 28, 1982, the J. Paul Getty Museum becomes the most richly endowed museum on earth when it receives a $1.2 billion bequest left to it by the late J. Paul Getty. The American oil billionaire died in 1976, but legal wrangling over his fortune by his children and Families.
1990S
1993
ATF raids Branch Davidian compound
At Mount Carmel in Waco, Texas, agents of the U.S. Treasury Department’s Bureau of Alcohol, Tobacco, and Firearms (ATF) launch a raid against the Branch Davidian compound as part of an investigation into illegal possession of firearms and explosives by the Christian cult.
U.S. PRESIDENTS
1844
Tyler narrowly escapes death on the USS Princeton
On February 28, 1844, President John Tyler cruises the Potomac with 400 others aboard the U.S. Navy’s new steam frigate USS Princeton, not realizing that his life will soon be in danger. In attendance that day were political dignitaries and their guests.
WESTWARD EXPANSION
1861
Congress creates Colorado Territory
With the region’s population booming because of the Pike’s Peak gold rush, Congress creates the new Territory of Colorado. When the United States acquired it after the Mexican War ended in 1848, the land that would one day become Colorado was nearly unpopulated by Anglo settlers.
ART, LITERATURE, AND FILM HISTORY
1983
Final episode of M*A*S*H airs
On February 28, 1983, the celebrated sitcom M*A*S*H bows out after 11 seasons, airing a special two-and-a-half hour episode watched by 77 percent of the television viewing audience. It was the largest percentage ever to watch a single TV show up to that time.
COLD WAR
1987
Gorbachev calls for nuclear weapons treaty
In a surprising announcement, Soviet leader Mikhail Gorbachev indicates that his nation is ready to sign “without delay” a treaty designed to eliminate U.S. and Soviet medium-range nuclear missiles from Europe. Gorbachev’s offer led to a breakthrough in negotiations.
AMERICAN REVOLUTION
1784
John Wesley charters first Methodist Church in U.S.
On February 28, 1784, John Wesley charters the first Methodist Church in the United States. Despite the fact that he was an Anglican, Wesley saw the need to provide church structure for his followers after the Anglican Church abandoned its American believers during the American crisis.
WORLD WAR II
1944
Test pilot Reitsch pitches suicide squad to Hitler
Hanna Reitsch, the first female test pilot in the world, suggests the creation of the Nazi equivalent of a kamikaze squad of suicide bombers while visiting Adolf Hitler in Berchtesgaden. Hitler was less than enthusiastic about the idea. Reitsch was born in 1912 in Hirschberg.
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