Science Timeline

Events

Science Timeline

1860 - 2000

Gregor Mendel Showed the characteristics of pea plants are passed along in a predictable way. He is considered the "Father of genetics"

1865

Frederick Miescher Describes an acidic substance ina a cell's nuclei. Now identified as DNA

1869

Walter Sutton showed that chromosomes carry the cell's unit of inheritance

1903

Thomas Hunt Morganhe concluded that (1) some traits were sex-linked, (2) the trait was probably carried on one of the sex chromosomes, and (3) other genes were probably carried on specific chromosomes

1911

William Asbury takes x-ray diffraction pictures of DNA

1943

Oswald Avery, Colin Maclead, and Maclyn McCarty Showed the substance that Griffith discovered is DNA

1944

Barbara McClintock discovers that genes can move around on a chromosome

1944

Erwin Chargaff Analysed the base composition of DNA in cells. He discovered that the amounts of adenine and thymine are almost always equal,as are amounts of guanine and cytosine.

1950

Alfred Hershey and Martha Chase Confirmed that the genetic material of viruses is DNA

1952

Rosalind Franklin Records a critical x-ray diffraction pattern, demonstrating that DNA is in the form of doble helix

1952

James Watson and Francis Crick Published their model of DNA doble helix

1953

Joe Hin Tjio defines 46 as the exact number of chromosomes in human cells

1955

Vernon Ingram discovers that a specific chemical altercation in a hemoglobin protein is the cause of sickle cell disease

1956

Arthur Kornberg produced DNA in a test tube

1957

Charles Darwin publishes The Origins of Species

1959

F. Sanger developed sequencing procedure for DNA

1963

Marshall Nirenberg is the first person to sequence the bases in each codon

1965

Paul Berg produced the first recombinant DNA molecule

1972

Scientists begin submitting DNA sequence data to a National Institutes of Health (NIH) database that is open to the public

1982

A genetic maker for Huntington's disease is found on chromosome 4

1983

Gene therapy was used on patients for the fist time

1990

Dr. Kary Mullis discovered the PCR procedure, for which he was awarded Nobel Prize

1993

Dolly "The Sheep" the first adult animal clone

1997

Craig Venter and Francis Collins announced the draft DNA sequence of the human genome at a White House ceremony in D.C.

2000