Important discoveries in genetics

Main

principles

1866

Gegor Mendel establishes principles of genetics

Nettie Stevens Edmund Wilson

1905

Independently described the behavior of sex chromosomes-XX determines female; XY determines male.

Genes Control Biochemical Events

1930

George Beadle and Edward Tatum discover through experiments on neurospora, a bread mold, that genes are responsible for the production of enzymes. Their report is the genesis of the "one gene-one enzyme" concept.

Jumping genes

1940

It was discovered in 1940 that some genes can jump.

Structure

1952

Scientists prove that DNA alone is the substance that transmits heredity, and that it has a spiraling, double-helix structure

Cracking the Genetic Code

1960 - 1969

Marshall Nirenberg leads the team that discovers the genetic code, showing that a sequence of three nucleotide bases (a codon) determines each of the 20 amino acids.

DNA repairs itself

1964

Philip Hanawalt of stanford and Richard B. of Oak Ridge National shows that DNA repairs itself

Recombining

1972

Ron Davis and Janet Mertz discover restriction endonucleases, essential for cleaving and “recombining” DNA.

Ronald levy

1992

In a step toward a cancer vaccine, Ronald Levy stimulates cancer patients’ immune systems with genetically engineered vaccines grown from their own tumors

Humans Have 20,000 to 25,000 Genes

2003

It was discovered that there are 20,000 to 25,000 genes in a human body.