The maize geneticist Barbara McClintock (1902-1992) is credited with the discovery of "jumping genes," that is chromosomal "crossing over" and translocation. She received the Nobel Prize in Physiology or Medicine in 1983. The collection is organized into six series: I. Correspondence, 1931-1991; II. Subject files, 1938-1989; III. Works by McClintock, 1944-1989; IV. Works by others, 1927-1991; V. Research notes, notebooks, and card files, 1930s-1990s ; VI. Photographs, 1928-1991.

A bacteriologist from MIT, Salvador E. Luria's work with Max Delbruck on bacteriophage demonstrated that bacterial resistance to certain phages arose through genetic mutations. His later work showed that phages also mutate genetically. He received the Nobel Prize in Physiology or Medicine in 1969 with Max Delbruck and Alfred D. Hershey. The collection is organized into seven series: I. Correspondence, 1938-1992 ; IIa. Subject Files, 1938-1990 ; IIb. Personal Material. 1923-1991 ; III. Works by Luria, 1938-1987 ; IV. Works by Others, 1944-1990 ; V. Research Notes and Notebooks, 1941-1979 ; VI. Course Material, 1931-1991 ; VII. Photographs and Negatives, 1957-1982. Arrangement: Alphabetical by folder title and then chronological within each folder.

A biochemist at Columbia University, Erwin Chargaff discovered the base-pairing regularities or "complementarity relationships" of nucleic acids that provided one of the key steps in developing a structural model for DNA. During his long career, Chargaff is credited with conclusively falsifying the tetranucleotide hypothesis; demonstrating the existence of a large number of DNA species; and creating the first descriptions of hypochromicity, hyperchromicity, and the denaturation of a DNA. In addition, Chargaff conducted important research on blood coagulation, lipids and lipoproteins, the metabolism of amino acids and inositol, and the biosynthesis of phosphotransferases. He retired to emeritus status in 1974 and remained active in research almost to the time of his death in June 2002. The Chargaff Papers are organized into ten series: I. Correspondence, 1931-1992; Ia. Correspondence, 1949-2002; IIa. Grants, 1930-1982; IIb. Subject Files, 1940-1984; IIc. Subject Files, 1946-2002; III. Works by Chargaff, 1929-1989; IIIa. Works by Chargaff, 1923-2002; IIIb. Reprints, 1977-1999; IV. Works by Others, 1936-1985; IVa. Works by Others, 1976-2002; V. Research Notes and Notebooks, 1929-1951 ; VI. Photographs, 1935-1977; VIa. Photographs, 1928-2002; VII. Audiovisual Materials; VIII. Awards and Certificates, 1958-2001; IX. Lecture Notes, 1942-1985; X. Personal Papers, [1880]-1985.

Ernst Wolfgang Caspari was an important contributor to behavior and developmental genetics, working primarily on the mealmoth Ephestia. Trained in Alfred Kuhn's laboratory at the University of Göttingen (1933-1935), Caspari was forced from his position by the Nazis in 1933, escaping to the United States five years later. As a professor of biology at Lafayette College, Wesleyan University, and the University of Rochester, Caspari continued his research on Ephestia, mouse genetics, and behavior genetics until his retirement in 1975. The Caspari Papers includes correspondence, papers, grant reports, and lectures relating to Caspari's genetic research dating primarily from the period after his departure from Germany. In addition to substantial material on behavior genetics and human evolution, the collection includes correspondence relating to Caspari's editorial work for Advances in Genetics, and his involvement with the American Institute of Biological Sciences, the Center for Advanced Study in the Behavioral Sciences, Cold Spring Harbor Laboratory, Fifth Banff Conference on Theoretical Psychology, Genetics Society of America, International Conference on the Unity of Science, Social Science Research Council, Committee on Genetics and Behavior, and the U.S. Atomic Energy Commission.

Between 1968 and 1978, the historian of science Horace Freeland Judson conducted extensive oral history interviews with biochemists and molecular biologists relating to the development of their field. The correspondence, transcripts of interviews, and taped interviews that comprise the Judson collection formed the research material used by Judson in his book, The Eighth Day of Creation (New York, 1979). Permission to quote must be obtained from Dr. Judson and access to some files is restricted.

The Papers of Curt Stern include extensive correspondence, lectures (1920s-1970s, 1.5 boxes), autobiographical material, articles, zoological course notes, photographs, etc. Stern's various areas of scientific interest are documented in the collection: the chromosome theory of heredity, role of gene mutation and chromosome rearrangements in evolution, action and interaction of genes during individual development, and particularly his contribution to the development of human genetics as a discipline (centered on his popular and influential book, Principles of Human Genetics, 1949, 1960, 1973). Both his career in Germany and the United States is documented in his correspondence. After studying with T. H. Morgan at Columbia University on a Rockefeller Foundation Fellowship (1924-1926), Stern returned to Richard Goldschmidt's lab at the Kaiser-Wilhelm Institute (1926-1932). There is material of note in the collection concerning this period when Stern helped to establish the cytological basis of crossing over. After a short stay at the California Institute of Technology in 1932, Stern's temporary residence in the U. S. became permanent, and his later career at the University of Rochester, 1933-1947 (Chairman, Department of Zoology) and at the University of California, Berkeley, 1947-1970 (there is abundant material on the Department of Zoology) is covered in the collection. There is other material on: American Association for the Advancement of Science Inter-Society Committee on Science Foundation Legislation, 1946-1947; American Society of Human Genetics (Pres., 1957); Atomic Energy Commission (Advisory Committee for Biology and Medicine, 1950-1955); Genetics (journal); Oak Ridge National Laboratory (Advisory Committee for Biology, 1955-1968); and the Rockefeller Foundation. Stern's correspondence with friends and colleagues in Germany, England, and the U. S., during the 1920s-1930s, is of particular note as it documents not only the developments in genetics and the institutional and administrative networks supporting research, but it also offers general comments and observations on science, Germany, and politics. The photographs (2 boxes) include pictures of many prominent geneticists and scientists.