1970
		1970
		1971
	Christian B. Anfinsen, Stanford Moore, and William H. Stein share a Nobel Prize in Chemistry, with Anfinsen cited for his work on ribonuclease, especially concerning the connection between the amino acid sequence and the biologically active conformation, and Moore and Stein cited for their contribution to the understanding of the connection between chemical structure and catalytic activity of the active centre of the ribonuclease molecule.	1972
		1973
		1974	Under mounting impeachment pressure resulting from the Watergate breakin, Nixon becomes the first president ever to resign from presidency. Gerald Ford becomes thirty-eighth president of the United States.
	David Baltimore, Renato Dulbecco, and Howard Temin share Nobel Prize in Medicine for their discoveries concerning the interaction between tumour viruses and the genetic material of the cell.	1975
		1976
		1977	Jimmy Carter becomes thirty-ninth president of the United States.
	Werner Arber, Dan Nathans, and Hamilton Smith share a Nobel Prize in Medicine for the discovery of restriction enzymes and their application to problems of molecular genetics.	1978
		1979
		1980