Alexander Hollaender was a leading researcher on the genetic effects of radiation. Born in Samter, Germany, in 1898 and arriving in the United States in 1921, Hollaender was educated at the University of Wisconsin, receiving his AB, MA, and Ph.D. there. He served on the faculty at the University of Tennessee and the University of Tennessee-Oak Ridge Graduate School of Biomedical Sciences. He was director of the division of biology at the Atomic Energy Commission's Oak Ridge National laboratory from 1946 until 1966. The 4 linear feet of the Alexander Hollaender Papers contain incoming and outgoing correspondence and reports relating to the genetic effects of radiation, specifically atomic radiation. Also included are documents of the International Conference on the Peaceful Uses of Atomic Energy; the NAS Committee on the Biological Effects of Atomic Energy, Genetics Panel; the United Nations Scientific Committee on Atomic Radiation; and the World Health Organization all of which Hollaender was closely involved with.

This collection is primarily correspondence and also notes on experiments concerning the cytology research of Lewis and his wife, Dr. Margaret Reed Lewis, at Johns Hopkins University, Carnegie Institution of Washington, and finally at the Wistar Institute of Anatomy and Biology in Philadelphia. There is significant material relating to his professional society activity in the American Association of Anatomists (President, 1934-1936) and the International Society for Experimental Cytology.

This miscellaneous collection relates to numerous topics in genetics: cattle breeding (especially the American Jersey Cattle Club), longevity, radiation, International Congress of Genetics (the 10th, 11th, and 13th), Gregor Mendel, aid for refugee scientists, and the records of the Genetics Society of America (1947-1974). The photographs series accession # 1968 433pr, was added to the finding aid in 2016.

The geneticist Milislav Demerec emigrated from Yugloslavia in 1919, spending nearly his entire career in the Department of Genetics at Cold Spring Harbor Laboratory. Working initially on the genetics of maize and later on Drosophila virilis, his research interests included radiation and chemical mutagenesis, and during the Second World War, penicillin and the genetics of antibiotic resistance. Demerec served as head of the laboratory at Cold Spring Harbor from 1941 until 1960. The Demerec collection contains the extant professional papers of Milislav Demerec, dating primarily from the time of his arrival at Cold Spring Harbor until his retirement. In addition to his correspondence with colleagues, the collection includes interesting material on the administration of Cold Spring Harbor laboratory during the 1940s and 1950s, data and research notes, material relating to professional organizations (e.g. Genetics Society of America, American Society of Naturalists), a lengthy series of lectures given by Demerec, and a large number of photographs pertaining to Demerec's research, but also to his colleagues and Cold Spring Harbor itself. There is also a Register of visitors to the laboratory (1927-1945) and a Milislav Demerec reprint list.